solenoide de control del turbo. -...

Hola amigos. Aunque no posteo mucho, os leo bastante amenudo y procuro enterarme de los bricos que salen y los problemas que va teniendo el Path. Os voy a contar mi caso completo, aúna riesgo de dar un poco la chapa, ya que yo agradezco leer los posts largos de algunos de los de

aquí

Hasta que me compre mi Pathfinder (un FE con 90000 km) yo lo mas complicado que habia hecho de mecanica era repostar combustible, pero viendo los bricos me animé con el refuerzo del tubo del turbo, y después me atreví a desmontar el intercooler y lavarlo con gasolina, y a sacar y sacudir los filtros del aire acondicionado.

En definitiva, sigo sin saber mucho de mecánica pero he perdido el miedo a tocar un poco algunas cosas.

Hace poco, se me fue el embrague y le he cambiado el volante por el macizo (1570 euros en la casa, aun me duelen).Desde entonces, el coche no funcionaba como antes. Se le notaba poco potente, aunque yo, queno soy muy sensible para esas cosas, no estaba del todo seguro. Simplemente estaba mosqueado y me daba "la sensacion" de que el coche no tiraba como antes. "Antes" es hace mucho tiempo, cuando el embrague aún no patinaba, puesto que estuve varios meses con el embrague patinando cada vez más.

Además, el coche soltaba bastante humo negro al pisarle entre las 2100 y las 2600 rpm. No humeaba casi si le pisaba por debajo de ese régimen, ni si le pisaba por encima. Sólo en ese rango.

Lo llevé a la Nissan, le pincharon el ordenador pero no les decía nada (normal, tampoco me sacaba ninguna luz en el cuadro) Me dijeron que podría ser el caudalímetro, pero que lo llevara pidiendo cita. Yo, por mi cuenta, también había leído que el fallo del caudalímetro puede dar mis síntomas. Me atreví a desmontar el mio (realmente sencillo, dos simples tornillos) y limpiarlo, yaque tras mucho leer, la gente por lo visto los limpiaba con alcohol. Por suerte no se estropeó nada, pero tampoco se arregló. Da la casualidad que mi vecino tiene también un Pathfinder y accedió a prestarme su caudalímetro. El comportamiento no cambió, así que caudalímetro descartado.

Poco después, en mi empresa compraron para hacer pruebas para otro proyecto, unos lectores de OBD. El típico cable VAG-COM, y otros inalámbricos (bluetooth). Todo comprado en DealExtreme, que es bastante barato, por cierto. Aproveché para pillar uno de los inalámbricos, y descubrí que hay una aplicación por ahí para teléfonos Android que se conecta a prácticamentecualquiera. Se llama Torque, y hay una versión gratuita que a mi me ha bastado para investigar un poco.

El programa permite monitorizar muchos parámetros, entre ellos el "boost" (viene en inglés) queviene a ser la presión del turbo. Me dí cuenta de que en mi coche, el turbo no soplaba nada hasta casi las 2000 rpm. Allí, se ponía a soplar a 0,3 bar y subía lentamente hasta llegar a los 0,6 bar a las 3000 rpm. Lo comparé con el seat ibiza de mi mujer y el renault megane de un compañero de trabajo, y los dos empezaban a soplar mucho antes (sobre las 1500) y se ponían a 1 bar hacia las 2000.

En mi Pathfinder era imposible conseguir que el "engine load" (carga del motor) llegara al 100%,y en los otros se consegía según pisabas el acelerador a fondo. Estaba claro que el turbo soplaba, pero que no lo hacía cuando debía, así que las sospechas se dirigieron hacia la válvula

solenoide de control del turbo.

Llevaba días abriendo el capot y viéndola allí, tan "hundida" (para mi si no está arriba del todo, es casi "inaccesible" xD). Le había apretado un poco los tubitos, para ver que tal van, pero no me había atrevido a hacerle nada más. También leí a un tipo que hablaba sobre como comprobarlos solenoides:http://www.rx7club.com/showthread.php?t=802060. Yo no tengo bomba de vacío, y tampoco tengo tubitos para engancharlos al compresor, pero me decidí a sacar la válvula y probar a meterle corriente, al menos para ver si suena. No fue difícil sacarla de donde está, lo que fue difícil fue atreverse a desconectar las 3 mangueras de vacío, iguales, con la esperanza de saberlas reconectar luego. Una vez sacada, la limpié todo lo posible y luego soplé apulmón por los tubitos, para ver qué pasa. Supongo que no es lo más higiénico xD. La sacudí para ver si está totalmente agarrotada, pero se movía. Le di corriente (sin importar la polaridad)aumentando desde 4,5 - 6 - 7,5 - 9 Voltios y se oía que se mueve y se la veía vibrar.. El tio explica que al dar/soltar corriente la válvula tiene que moverse instantáneamente, y eso sólo pasaba cuando le apliqué 9 V. El coche, entiendo, aplica 12, así que debería irle bien.

Volví a instalar la válvula, sin haberle hecho realmente nada. Soplarle y succionarle por todos losconductos, sacudirla... nada.Lo complicado fue enganchar de nuevo las mangueras, que son iguales. OUT (viene escrito en la válvula) es la salida, y va al turbo. Se puede seguir esa manguerita. ATM es la que va a la admisión, y también se puede segiur. La que queda es VAC, que es la manguera que se va por detrás del motor, así que es la que conecté al final.

Misteriosa/milagrosamente, cuando salí a probar qué tal había ido el asunto, el coche andaba como yo lo recordaba. El turbo empieza a soplar hacia las 1600 rpm y se pone rápidamente a 1 bar, llegando a medirse un pico de casi 1,4 bar. Al pisar a fondo se pone enseguida en 100% de carga de motor, igual que los otros coches. No se ve por el retrovisor nada de humo, pises lo quepises, al régimen que sea.

Supongo que antes o después esa válvula volverá a fallar, ya que debe estar tocada de algún modo, pero al menos ya sé que el problema viene de allí y que sólo tengo que comprar otra válvula, si desmontarla y sacudirla un poco no basta. Espero que a alguno le pueda servir mi experiencia. A los que no, perdón por el ladrillo xD

http://www.rx7club.com/showthread.php?t=802060

El tema de la valvula EGR parece preocupar a muchos usuarios,no es para

menos debido a las consecuencias que va a traer al motor a partir sobre todo de los 40y 50.000kms. El dichoso sistemita de recirculacion de gases ,en mi opinion es una forma de reducir emisiones contaminantes (NoX) a costa del bolsillo del usuario y de la vida util del motor. El tema contaminacion depende de la etica de cada uno ,pero desde luego no voy a seryo quien a costa de mi dinero subbencione las burradas contaminantes en la politica depaises que se niegan a cumplir por ejemplo el protocolo de kioto(Normativas Internacionales Emision Gases Contaminantes).Politica a parte, el volver a introducir parte de los gases de escape otra vez en el motorno es ni mas ni menos que una BURRADA TECNOLOGICA de unos cuantos ILUMINADOS.Existen otros sistemas que no dañan ni ensucian tanto el motor ni le restan potencia. Consecuencias de volver a introducir gases quemados en el motor : -disminucion de Oxigeno disponible y merma de potencia . -anulacion de parte de la eficacia del intercooler (enfria los gases para que luego el sistemita EGR los vuelva a calentar ????. -ensuciamiento de la propia valvula EGR y del conducto de admision, que a partir de los 40 o 50000 km requiere limpieza de hollines depositados. -ensuciamiento interno del motor:el aceite retiene mas hollines y se ensucia mas perdiendo eficacia Y PROVOCANDO MAYOR DESGASTE AL MOTOR .El sistema de las valvulas de admision 16V va perdiendo eficacia a lo largo de los km debido a los hollines depositados en las CABEZAS DE VALVULA AFECTANDO AL ASIENTO DE ESTA Y

LA LA VELOCIDAD DE PASO DEL AIRE A LA CAMARA DE COMDUSTION. Como podeis ver no voy a ser yo quien lleve el coche a la NISSAN para que me hagan el mantenimiento de todo este DESAGUISADO. SOLUCION que llevo INSTALADO en mi pathfinder con optimos resultados y sin AFECTAR A LA ELECTRONICA de gestion del motor: -Se trata de engañar ala centralita electronica del motor y al mas experto de los mecanicos y de no ser detectado en el vano motor: -Para ello vamos a sustituir la JUNTA que hay entre el conducto que viene de los colectores de escape (tuberia de acero INOX) Y LA ENTRADA DE LA BASE DE FUNDICION DE LA EGR. -Desmontada la base extraes la junta y te fabricas otra EXACTAMENTE IGUAL PERO ENCHAPA DE ACERO INOX DEL MISMO ESPESOR QUE LA ORIGINAL PERO _CIEGA_. -Para fabricar esta junta CIEGA solo necesitas unas tijeras de chapa ,un trocito de chapa de inox,una lima de 1/2 caña ,un taladro y una broca .Copias la junta original sobre la chapa y la recortas y le das los dos taladros. Como puedes ver una vez montado todo el conjunto ,no se nota absolutamente nada yla valvula EGR va a seguir funcionando igual pero sin que le pase todos los gases provenientes de la combustion. -Para desmontar la valvula EGR QUITAS EL CONECTOR Y LOS 4 TORNILOS y la extraes,notaras que se engancha un poco pero tiras y sale . -El tema de la TEMPERATURA DE LA COMBUSTION no vas a tener problemas por que todos los motores actuales estan preparados , de hecho cuando la EGR esta en funcionamiento es sobre todo al ralenti pues cuando aceleras fuerte y vas en altas RPMla valvula va cerrada permitiendo maxioma potencia y por lo tanto max. temp .en camaras de combustion. POR SI OS VALE llevo funcionando con este sistema 25000 km y lo unico que he notado: -Mas par motor en bajas rpm. -ausencia total de tirones. -mas aceleracion desde parado. -Ningun problema electronico. -CONSUMO invariable y estable respecto al oficial. -Mayor capacidad de recuperacion en general en toda la gama de velocidades . -EN DEFINITIVA ya he pagado bastante dinero por el coche como para permitirme el lujo de seguir financiando a los servicios oficiales de la marca a costa de mi tiempo y dinero.

Con respecto a los INGENIEROS te comento que si pienso que no dan la talla,la mecanica se invento hace mucho y los ingenieros se supone estan para mejorarla no para empeorarla, como por ejemplo con el sistema EGR:¿como te explicas que coloquen un intercooler para refrigerar el aire de admision y con ello ganar potencia y luego van y le meten gases quemados a alta temperatura en la camara de combustion por medio de la EGR?.Si ya se que si la contaminacion y lo demas ,pues como te demuestra el articulo LO QUE GANAN POR UN LADO ,LO PIERDEN POR OTRO .NO puede ser que para evitar unos gases malos potenciemos otros gases peores:Y DE

PASO PERJUDIQUEMOS TODA LA MECANICA.Volver arriba

Hola a todos!

Después de leer el anterior post sobre el tema y de investigar un poco por mi cuenta, paso a contarosun sistema más fácil para anular la EGR.

La EGR es una válvula de recirculación de gases. Su misión esponer en comunicación el sistema de escape con el de admisión para que el motor respire gases muy empobrecidos en oxígeno. Esto es para evitar la formación de óxidos denitrógeno NOx que son gases nocivos y contaminantes que se forman en presencia de abundante

oxígeno. Esta válvula sólo funciona en cargas parciales (es decir, cuando no le pedimos carga o "caña" al motor) y siempre que no esté soplando el turbo (ya que la presión de éste se nos iría hacia el escape).

La implantación de esta válvula viene por la normativa europea anticontaminación ( con la que estoymuy a favor). Sin embargo nos provoca también un problema mecánico de funcionamiento: Los gases quemados que vienen del sistema de escape son muy ricos en carbonilla (tan típica de los diesel) y esta carbonilla hace algo parecido en nuestro sistema de admisión

como el colesterol en las venas..... Los conductos se van taponando hasta que no pueden más y entonces.... al taller a pagar!

Lo que os propongo aquí es un sistema para evitar esta acumulación de carbonilla y eliminarlos taponamientos y los pasos innecesarios por el taller a costa de producir NOx a la atmósfera y a nuestros pulmones (que me perdonen los ecologistas....)

Este sistema se encuentra en la parte delantera del motor debajo del colector de admisión ( se puede ver sin desmontar).

a él llega una tubería que viene de la culata y va hasta ella.

Lo que propongo es sustituir la juntaque une la tubería a la válvula por una fabricada por nosotros mismos. Esta nueva la he fabricado de chapa de 0`8 mm aunque lo mejor sería de aluminio y llevará sólo los agujeros

de los tornillos y no el agujero de paso central (taponando la entrada de gases quemados hacia la válvula).

Con esto, la válvula nunca dejará de funcionar (por lo tanto no hay fallo). Simplemente, no llegan gases quemados a ella. El caudalímetro no tiene la función de diagnóstico sobreel flujo de aire de entrada por lo tanto tampoco se da cuenta del engaño.

Os puedo decir que yo lo he hecho yfunciona todo perfectamente.A ver sicon esto os puedo ayudar a ahorrar una pasta en taller y muchos doloresde cabeza.

Mass Air Flow (MAF) Sensor Test 3.3L Frontier, Quest, Pathfinder, XTerra

-Part I-

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This type of MAF Sensor is used on the 3.3L V6 Nissan engine. So if you need to test the Mass Airflow Sensor on a Nissan Quest, or a Pathfinder, or a Frontier or anXterra... this is the article for you.

You'll find step by step instructions on how to test this 'hot-wire' type Nissan MAF Sensor. Before jumping into the tests, read this section first. Here you're gonna' find some important tips and suggestions so that you can successfully diagnose the MAF on your Nissan car or truck.

Common Symptoms of a BAD Nissan MAF Sensor

These are some of the most common symptoms of a BAD Nissan MAF Sensor:

1. A MAF Sensor code that lights up the Check Engine Light (CEL), but not always.

2. Lean and/or Rich code(s).3. Fuel Trim code(s).4. A tremendous lack of power upon acceleration.5. Black smoke coming from the tail-pipe.6. Won't an Emmissions Test.7. Vehicle may idle rough and stall.8. BAD gas mileage.

Is my MAF Sensor just Dirty?

There's a good chance that the MAF Sensor on your Pathfinder (or Quest, or Xterra, or Frontier) is just dirty. Dirty? OK, that the MAF Sensor's 'hot-wires' are contaminated with dirt and/or oil.

When the MAF Sensor does get dirty (contaminated), it usually doesn't cause a tremendous amount of havoc. The two biggest symptoms of dirty MAF Sensor are 1) a lack of power upon acceleration and 2) BAD Gas mileage (although this is not an absolute truth).

Why does it get dirty/contaminated? Well, this MAF Sensor easily becomes contaminated with dirt and stuff from the air filter not performing its job or the box that holds the air filter is broken or not sealing correctly. Cleaning this type of Sensor is very very easy and the last section of this article shows you just how.

What tools do I need?

A Digital Multimeter is gonna' be your best friend in testing the MAF Sensor on yourXterra (or Quest, or Pathfinder, or Frontier). You don't need a fancy one, since all you'll be doing with it is verifying DC voltages.

Circuit Descriptions of the Frontier, Quest, Pathfinder, Xterra MAF Sensor

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The MAF Sensor on your Frontier (or Quest, or Pathfinder, or Xterra) has the letters A through D etched onto it. These letters identify the circuits that feed into itsconnector. I'll be using these very same letters to describe the circuits (since the color of the wires will not be the same, on your Nissan vehicle, as those in the photos).

1. Letter A1. Empty slot in the connector.

2. Letter B1. 12 Volt Battery Power.

3. Letter C1. Ground. Provided by the ECM internally.

4. Letter D1. MAF Signal.

The safest way to test these circuits, and the method I always use, is using a wire piercing probe. (click here to see a picture of this tool). Using this probe, I don't

http://easyautodiagnostics.com/tools_n_stuff/wire_piercing_probe.php

have to disconnect the MAF Sensor's connector to probe the front of the female terminal and possibly risk damaging it.

Independent of the method you use, be careful not to damage the wire or the female terminal. Take all safety precautions.

First Things First

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You're starting point (in testing the MAF Sensor) is to see if it's dirty. Why? Well, because checking to see if this MAF Sensor is Dirty (Contaminated) is so easy on these Nissan vehicles. Not only that, you just might save yourself some time by cleaning it first (if it's dirty, that is).

If the MAF Sensor is dirty, then TEST 1 will show you how to clean it. Go to TEST 1.

Nissan Application Chart

1. Frontier 3.3L

1. 1999, 2000, 2001, 2002, 2003, 20042. Quest 3.3L

1. 1999, 2000, 2001, 20023. Pathfinder 3.3L

1. 1998, 1999, 20004. Xterra 3.3L

1. 2000, 2001, 2002, 2003, 2004


-Part II-

TEST 1: Checking for aDirty (Contaminated) MAF Sensor

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The very first thing to do is to remove the Mass Airflow Sensor (MAF) Sensor from its housing and eyeball the two 'hot-wires' in the MAF Sensor.

The two hot-wires are normally an off-white to a light gray color, so if they're dirty (contaminated) they will be covered in what appears to be a black fuzz.

We can't just use any type of solvent to clean the MAF Sensor with. Here are a couple of very important guidelines on what to use:

1. An Electronics Spray Cleaner can be used.a. You can buy it at your local autoparts store (Autozone, Pepboys,

O'Reilly, etc).b. You can buy it at your local electronics store (Radio Shack, Fry's,

etc).2. Or you can buy a MAF Sensor cleaning spray. Yes, there is one designed just

for cleaning MAF Sensors.a. This cleaner is made by CRC Industries and its part number is:

05110.b. You can buy it at your local autoparts store (Autozone, Pepboys,

O'Reilly, etc).

3. Don't use carburator or brake clean spray or gasoline.a. These solvents will leave a residue on the wires that will attract

dust/dirt and you're back to square one in a few weeks or months.

b. Not to mention the harsh solvent can damage the MAF Sensor's electronics.

4. Also, don't attempt to physically clean the sensor with anything (like a cotton swab) or you may break the wires.

If the MAF Sensor hot-wires were not dirty (contaminated), then re-install the MAF Sensor back onto its housing and go to TEST 2.

If the MAF Sensor hot-wires were dirty (contaminated), clean per the suggestion given above. Then re-install the MAF Sensor back onto its housing and road test your Nissan to see if the issue has been solved. If the issue was not solved... then further testing is required, go to TEST 2.

TEST 2: Testing The Power Circuit

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The very first thing that we'll do is check that the MAF Sensor is receiving 12 volts. The procedure I recommend for you to use (to accomplish all of the tests below) is to use a test probe that pierces thru' the wire's insulation (click here to see a picture of this tool). DO NOT insert anything into the female terminal.

Whatever method you use, the key here is not to damage the female terminal or the wire. Again,be careful. Use common sense and take all necessary safety precautions.

1. Put the multimeter in VOLTS DC mode.2. Do not disconnect MAF Sensor Connector from the MAF Sensor.3. With the RED multimeter test lead and an appropriate tool, probe the MAF

Sensor Connector's B circuit as shown in the photo.4. With the BLACK lead of the multimeter probe BATT (-) negative terminal.5. Turn Key On with the Engine Off.

You should see 12 Volts on the multimeter. Do you have 12 volts?

CASE 1: The Multimeter registered 12 Volts -All is good in the neighborhood, GO TO TEST 3.

CASE 2: The Multimeter DID NOT register 12 Volts -The MAF Sensor is not the problem. Without this voltage the MAF Sensor will not work.

TEST 3: Testing The Ground Circuit

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In the previous test we checked that the Sensor was receiving 12 Volts. Now we'll check that the MAF Sensor is getting a good ground. This Ground is provided by the ECM internally.

Be careful and take extreme care not to short-circuit this wire to ground or power as you're probing it.

You can test this circuit with the connector connected to MAF Sensor or not.

1. Turn key to the OFF Position.2. Put the Multimeter in VOLTS DC mode.3. With the BLACK multimeter test lead and a wire-piercing-probe, probe the MAF

sensor connector's C circuit as shown in the photo.4. Connect RED lead to the BATT (+) positive terminal.5. Turn the Ignition Switch to the RUN position.

You should see a voltage of 12 Volts. Do you have that?

CASE 1: The Multimeter registered 12 Volts -All is still good in the neighborhood.Go to Test 4.

CASE 2: The Multimeter DID NOT register 12 Volts -The MAF sensor is not the problem. Without a ground in this circuit, the MAF Sensor will not work.

http://easyautodiagnostics.com/nissan_maf_tests/quest_pathfinder_maf_3.php


-Part III-

TEST 4: Testing The MAF Signal

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Now that the basics have been checked, we'll check the MAF signal coming out of the sensor and going to the ECM. Here's a little background information to help you understand what you'll be doing in this test step.In a nutshell, the MAF Sensor measures the amount of air the engine is breathing and converts this measurement into a DC Voltage signal the PCM (Powertrain Control Module=Fuel Injection Computer) can use to calculate Fuel Injection. Specifically, the air that the engines breathes at idle (lets say an idle of 800 RPM's)is less than the air the engine needs at 2,700 RPM's. Therefore, the DC Voltage Signal the MAF Sensor will output to the PCM is less at idle than at 2,700 RPM.The important thing to know when verifying the MAF Signal is not to look for a specific MAF Signal Voltage reading a specific RPM but to verify that the DC Voltage signal rises smoothly when the engine is accelerated and returns to its initial DC readings when the engine returns to its idle.

The two most common results you'll get from a BAD Mass Airflow Sensor (MAF) Sensor. are: 1) NO VOLTAGE SIGNAL AT ALL for the MAF Signal output or 2) erratic voltages that don't correspond to the amount of air the engine is breathing as you accelerate or decelerate the engine.In case you're wondering, the working DC Voltage range of the MAF Signal is between .5 and 4.5 Volts. At idle the average voltage will be abut .9 to 1.6 volts depending on engine idle conditions. At around 2500 RPMs, you should a Voltage of 1.7 to 2.3 Volts DC.

OK, Here's the TestStart the engine and let it reach it's normal operating temperature. You'll be using the Voltage reading you will obtain at idle as a base to diagnose the MAF Sensor.The MAF Sensor must be connected to its connector to perform this test.

1. With the key in the OFF position.2. With a suitable tool connected to the RED multimeter lead, probe

the D circuit of the MAF Sensor connector shown in the photo.3. Put the multimeter in VOLTS DC mode.4. Connect the BLACK lead to the Battery (-) Negative Terminal.5. Start the already warmed up engine.6. Note the Volts reading on your multimeter at idle. This reading may be

stable (with only small fluctuations) or unstable with very extreme fluctuations. No matter what the instability in the reading, this will be yourbase reading.

7. Accelerate the engine as you watch the multimeter's Voltage readings.8. The Voltage numbers should correspond to the amount of acceleration.9. Repeat this as often as you need to verify that the Voltage numbers on

the multimeter rise smoothly every single time.10. If the MAF Sensor is good, these readings will not spike up and down

crazily but will correspond to the amount of air the engine is breathing at the different RPMs you're accelerating the engine to.

Did the signal rise smoothly with each increase in engine acceleration and stay steady at idle?CASE 1: The Multimeter registered the indicated Voltage -The MAF Sensor is functioning correctly.CASE 2: The Multimeter DID NOT register the indicated Voltage -The MAF Sensor is defective. Replace MAF Sensor.

Power Transistor Test & Ignition Coil Test3.3L Nissan (1996-2004)

-Part I-

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Testing a No Start-No Spark or a Misfire Condition on your Nissan Mini-Van or PickUp or SUV or the Mercury Villager (with the 3.3L V6 engine) is not difficult at all. Noexpensive tools or diagnostic equipment is needed, and this article will show you just how to do it step by step.With the tests in this article, you’ll be able to test and diagnose: A BAD Power Transistor, or a BAD Ignition Coil, or a BAD Distributor Cap, or BAD Spark Plug Wires on your Nissan vehicle.At the bottom of this page, you’ll find a complete list of Nissan and Infiniti models that this test article applies to.

Symptoms of a BAD Transistor, Ignition Coil, Spark Plug Wires, or Dist. Cap

If you’re Nissan SUV or mini-van is suffering a Misfire... the Check Engine Light (CEL) will be on to let you know that YES, there really is something wrong. Here are a couple of other symptoms your vehicle may experience with a Misfire Condition:

1. Diagnostic Trouble Codes (DTC) stored in the Computer’s (PCM) memory:

P0300, P0301, P0302, P0303, P0304, P0305, P03062. Misfire that does not light up the Check Engine Light (CEL).3. No Power.4. Idles Rough.5. BAD Gas Mileage.6. Black smoke coming out of the Tail Pipe.7. Rotten egg smell coming out of the Tail Pipe.8. Smell of unburned gasoline coming out of the Tailpipe.9. Won’t pass the State Emissions Test.

If the Power Transistor or the Ignition Coil is BAD, then the most common symptomis that your vehicle will CRANK but not START and there will be no Spark at any of the Spark Plug Wires.

Basic Nissan Ignition System TheoryTo be able to successfully diagnose a Misfire or No Start on your Nissan vehicle (whether it’ a pick up, SUV, or a mini-van) it’ll help to know how Spark is created and fed to the Engine Cylinders. This is what happens in a nutshell when you turn the key and crank the engine:

1. The Crankshaft Position Sensor and Camshaft Position Sensors startto generate and feed their Signals to the vehicle’s PCM (Powertrain Control Module=Fuel Injection Computer).

2. The PCM uses these Signals to know where each Piston is at in relation to its combustion cycle and with this info, the PCM knows when to start activating the Power Transistor, the fuel injectors and a host of other things to get your Nissan vehicle started.

The Power Transistor is the Ignition Control Module (ICM) in the Nissan vehicles.

The Power Transistor is located within the Distributor Assembly and is part of the Cam Sensor Assembly.

3. So then, after receiving the Crank (CKP) and Cam (CMP) Signals, the PCM sends the Power Transistor a Triggering Signal that tells thePower Transistor exactly when to activate the Ignition Coil.

4. The Power Transistor activates the Ignition Coil by opening and closing the Primary Current Circuit of the Ignition Coil... and as you may already be aware it’s this opening and closing action that makesthe Ignition Coil Spark away.

5. The Spark created by the Ignition Coil is fed to the Distributor Rotor directly by the Distributor Cap and then from there to each engine cylinder via a Spark Plug Wire.

With the simple and easy tests presented in this test article you’ll be able to find theexact cause of your Nissan vehicle’s Misfire or No Start Condition (if it’s Ignition System related) and in the process save time and money.


-Part II-

What Tools do INeed to Test the Ignition System?

Although the tests in this article are easy and simple, you do need some specific tools to perform them with. Here’s the list:

1. An HEI Spark Tester1. This inexpensive Spark Tester is a MUST have tool to be able to

correctly diagnose the Ignition System on your Nissan vehicle with the info and tests in this article (don’t have an HEI Spark Tester? Need to buy one? You can buy it here: KD Tools 2756 Ignition Tester Calibrated For HEI Ignitions).

Don't use a regular Spark Plug instead of a Spark Tester.

2. Battery Jump Start Cables.3. A Digital Multimeter that can read Hertz (Hz) Frequency.

1. Without a Multimeter that can read Hertz Frequency, you won’t be able to accomplish some of these tests. (don’t have a Digital Multimeter that can read Hertz frequency? Click here to see my recommendations: Buying a Hertz enabled Digital Multimeter).

4. A helper.1. You'll need someone to help you crank the engine while you

perform the tests in the engine compartment.b. A Repair Manual.

1. For whatever remove and replace info you'll need that is not covered by this article.

Power Transistor/Cam Sensor AssemblyCircuit Descriptions

http://easyautodiagnostics.com/multimeter_recommendation/digital_multimeter_hertz_1.php

http://www.amazon.com/gp/product/B0002STSBC?ie=UTF8&tag=easyautodiagn-20&linkCode=as2&camp=1789&creative=9325&creativeASIN=B0002STSBC

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There are 6 wires coming out of the main Distributor Connector. This connector connects to the Power Transistor/Cam Sensor Assembly that’s located within the Distributor.

Now, don’t worry, you don’t need to test all of them to diagnose this Ignition System. Below are the circuit descriptions of all six wires (circuits):

Circuit labeled 11. Triggering Signal for Power Transistor. This Signal comes from

the PCM. Circuit labeled 2

1. Ground Circuit for the Power Transistor. Circuit labeled 3

1. Camshaft Position Sensor Signal - 120° REF Signal. Circuit labeled 4

1. Camshaft Position Sensor Signal -1° POS Signal. Circuit labeled 5

1. Camshaft Position Sensor Power (12 Volts). Circuit labeled 6

1. Camshaft Position Sensor Ground.

Ignition Coil Circuit Descriptions

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The other connector has two wires coming out of it and both of these go directly to the Ignition Coil inside of the Distributor. Here are their Circuit Descriptions:

1. Circuit labeled 11. Power (12 V) Circuit.

2. Circuit labeled 21. Switching Signal output to the PCM.


-Part III-

TEST 1: Testing for Spark at the Spark Plug Wires

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The starting point of your Misfire or No-Start diagnosis is testing for Spark at the Spark Plug Wires. Now, you might already have a specific cylinder you want to testfirst (if you have a specific Misfire Diagnostic Trouble Code: P0300, P0301, P0302,P0303, P0304, P0305, P0306, P0307, P0308) or you just don’t know where to start. Well, my recommendation is to test all of the Spark Plug Wires for Spark regardless.

I want to stress the importance of using an HEI Spark Tester to perform all of the Spark tests. Here are a couple of other important suggestions:

1. Do not use a regular Spark Plug in place of a Spark Tester.2. Do not pull the Spark Plug Wire off of its Spark Plug while your helper

cranks the engine to verify Spark. This will damage the Ignition Coil, if it isn’t fried already.

OK, here we go:

1. Disconnect the Spark Plug Wire from its Spark Plug.

2. Attach the HEI Spark Tester to the Spark Plug Wire.3. With a Battery Jump Start Cable, attach the HEI Spark Tester to a good

Ground point or to the Battery Negative Terminal.4. Have your assistant crank the engine while you eye-ball the Spark Tester. If

you’re testing a Misfire Condition, the engine will start... so be careful.5. Repeat the test for all of the remaining Spark Plug Wires (if applicable).6. You’re going to see only one of two results: either Spark jumping across the

HEI Spark Tester’s air gap or No Spark.

CASE 1: If you got Spark on all of the Spark Plug Wires: This results let’s you know that the Power Transistor, Ignition Coil, Distributor Rotor and Cap are OK. Having all of the Spark Plug Wires firing off Spark eliminates all of these components as the cause of your Misfire Codes or No Spark- No Start Condition. For some suggestions as to what could be the cause of the Misfire Condition and/or Misfire Codes, go to TEST 8.

CASE 2: If you got NO Spark from any (none) of the Spark Plug Wires: The next step is check that the Ignition Coil is creating and feeding Spark to the Distributor Cap. You’ll accomplish in TEST 3. Go to TEST 3.

CASE 3: If you got Spark on some but not all of the Spark Plug Wires: The next step is check for Spark directly on the Distributor Cap towers that feed Spark to these Wires that did not fire off Spark. Go to TEST 2.

TEST 2: Testing for Spark at the Distributor Cap

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It’s not uncommon for a Distributor Cap to have one or more towers not transmitting Spark from the Distributor Rotor to their respective Spark Plug Wires. This problem, of course, this will cause a Misfire Condition.

This type of problem can be tested with a simple Spark test. In this test step, you’ll be testing for Spark with the HEI Spark Tester directly on the Distributor Cap tower (or towers) whose Spark Plug Wire did not fire off Spark in TEST 1.

Important: this test is only for when one or several (but not all) of the Spark Plug Wires did not Spark!

1. OK, un-plug the Spark Plug Wire (that didn’t Spark) from its tower on the Distributor Cap and place the Spark Tester directly on the tower.

2. With the same Battery Jump Start Cable you used in TEST 1, ground and hold the Spark Tester to the tower as shown in the photo.

3. Ask your helper to crank the engine while you observe the HEI Spark Tester.

4. Repeat this test with the others that did not fire off Spark (if applicable).

You'll see one of two results: the HEI Spark Tester Sparking or No Spark. Let's analyze each of these results below:

CASE 1: If you got Spark, Then the Spark Plug Wire is BAD, replace all of them as a set. This will solve your Misfire Condition and Misfire Codes lighting up your CHECK ENGINE LIGHT (CEL). Now, if the rest of the Distributor components (Distributor Cap and Rotor) are as old as the Spark Plug Wires you’re replacing... I recommend replacing them too.

Here's the why of the No Spark result: As the Spark Plug Wire gets older, its normal resistance to spark increases to the point that the it can’t and doesn’t

channel Spark to the Spark Plug. This will either cause a Misfire, or a lack of power, or a No Start Condition. Spark Plug Wires don't last forever, especially after-market ones (average life-span is 3 to 4 years).

CASE 2: If you got No Spark, This is a clear indication that the Distributor Cap is BAD. Replace the Distributor Cap and Distributor Rotor as a Set. This should solveyour misfire problem. Now, if the rest of the Distributor components (Spark Plug Wires and Spark Plugs) are as old as the Distributor Cap and Rotor you’re replacing... I recommend replacing them too.

Here's why: As the Distributor Cap ages, the terminals that transmit the Spark to the Spark Plug Wires corrode. This corrosion increases the resistance to Spark and over time (as more corrosion is created) this same corrosion stops the Spark from passing thru' to the Spark Plug Wires.


-Part IV-

TEST 3: Testing the Ignition Coil for Spark

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In this test step, you’ll test for Spark directly on the Ignition Coil’s tower. Since the Ignition Coil is inside the Distributor, you’ll need to remove the Distributor Cap.

Also, since the test is performed with the engine cranking, the Distributor rotor will rotate... so be careful and take all necessary safety precautions. In the photo you’ll notice the Distributor Rotor off the Distributor for safety reasons.

1. Place the HEI Spark Tester directly on the Ignition Coil’s tower.2. Now, ground the HEI Spark Tester with the same Battery Jump Start Cable

you have been using for the previous tests.3. When all is ready, have your helper crank the engine as you hold the HEI

Spark Tester in place.4. As before, observe the HEI Spark Tester to see if Spark jumps across its air

gap.

You'll get one of the 2 results: (1) Spark or (2) No Spark. Let's analyze each result in more detail below:

CASE 1: If the Spark Tester Sparked, this result confirms that the Distributor Capis BAD. Replace the Distributor Cap and Rotor as a set and your No Start Condition should be solved.

CASE 2: If the Spark Tester DID NOT SparK. Then further testing is required to see if the problem is due to a BAD Nissan Power Transistor or something else. You're gonna' find out with the rest of the tests, Go To TEST 4.

TEST 4: Ignition Coil’s Power (12 V) Circuit


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If you’ve reached this point, it’s because you’ve gotten a No Spark result from all ofthe Spark Plug Wires, the Distributor Cap and the Ignition Coil on your Nissan vehicle. In this test step you’re gonna’ verify that the Ignition Coil is getting a good supply of juice (10 - 12 Volts DC).

1. Select Volts DC mode on your Multimeter.2. With the RED multimeter test lead probe the wire identified with

the number 2 in the photo. This should be the Black with White stripe wire of the two wire Distributor Connector (the Distributor has one 6 wire connector and a 2 wire connector).

3. Connect the BLACK lead of the Multimeter to the Battery (-) Negative Terminal.

4. Ask your assistant to turn the Key On with the Engine Off.5. You should see 12 Volts on the multimeter. Do you have 12 volts?

CASE 1: If your Multimeter displayed 12 Volts, this is good since it let’s you know that the Ignition Coil is getting power, the next step is to check to verify that the Ignition Coil is being fed with the Switching Signal that comes from the Power Transistor... go to TEST 5.


CASE 2: If your Multimeter DID NOT display 12 Volts, you must find out why you're missing this voltage. Without this Voltage the Ignition Control Module (ICM) nor the Ignition Coil will work. Resolving this Power issue should solve your No Start - No Spark Condition.


-Part V-

TEST 5: Testing the Ignition Coil’s Switching Signal

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OK, as you may already know, the Power Transistor is the one responsible in activating the Ignition Coil to start Sparking away on your Nissan SUV (or Pick Up

or Mini-Van). It does this by a Switching Signal and this Signal can be easily tested with an LED Light. In this test step you’re gonna’ verify if indeed this signal is being supplied to the Ignition Coil. Alright, let’s get started:

1. This test must be done with both of your Nissan Distributor’s connectors connected.

2. Connect the BLACK lead of the LED Light to the wire (circuit) identified withthe number 1 in the photo. This should be the Blue wire of the two wire Distributor Connector (the Distributor has one 6 wire connector and a 2 wire connector).

3. Connect RED lead of LED to the Battery (+) Positive terminal. It isIMPORTANT that it be connected at the Battery Positive Terminal.

4. Have an assistant crank the engine.

If everything is working like it should, the LED Light will blink on and off the whole time the engine is being cranked. Don’t worry about what the LED Light does before or after your helper starts cranking the engine. The only results you’re interested in interpreting are the results obtained with the engine cranking.

CASE 1: If the LED flashed On and Off, then the Ignition Coil is BAD, replace it. This also means that the Power Transistor is GOOD. Replacing the Ignition Coil will solve your No Spark/No Start Condition. The only thing that sucks is that at the time of this writing, you cannot buy the Ignition Coil separately... you have to buy the whole Distributor.

CASE 2: If the LED DID NOT flash On and Off, re-check all of your connections and retry the test again. If still no light pulses on the test LED, go to TEST 6.

TEST 6: The Power Transistor’s Ground Circuit

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For the Power Transistor to activate the Ignition Coil, it has to have a good path to Ground and in this test will help you to verify that it does.

For this test you can use a Multimeter or a Test Light, although the test steps assume that you’re using a Multimeter:

1. Select Volts DC mode on your Multimeter.2. With the Multimeter’s BLACK test lead probe the wire identified with

the number 2 in the photo of the 6 wire Distributor Connector.3. Connect the RED lead of the Multimeter to the Battery (+) Positive

Terminal.4. You should see 12 Volts on the multimeter without having to turn the Key to

ON. Do you have 12 volts?

CASE 1: If your Multimeter displayed 12 Volts, this is good since it let’s you know that the Power Transistor has a good path to Ground, the next step is to check to verify it’s receiving a Triggering Signal from the Fuel Injection Computer... go to TEST 7.

CASE 2: If your Multimeter DID NOT display 12 Volts, then there’s a problem with the Ground circuit. Without Ground the Power Transistor cannot activate the Ignition Coil to start Sparking. Resolving this Ground issue should solve your No Start - No Spark Condition.


-Part VI-


TEST 7: Testing the Triggering Signal from PCM

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For the Power Transistor to activate the Ignition Coil, it has to receive the instructions do so from the Fuel Injection Computer. This is done by a Signal calledthe Triggering Signal (although this is not Nissan’s technical name for it).

In this test, you’re gonna’ check to see if the Power Transistor is being supplied with it when the engine is being cranked. For this test you’ll need to use a Multimeter that can read Hertz Frequency... an LED Light will not work here since the signal’s frequency is so fast that you can not see it with an LED Light. OK, let’s get started:

1. It’s important that the Battery be in a fully charged condition for this test.2. Select Hertz (Hz) Frequency mode on your Mulitmeter (don’t have a Digital

Multimeter that can read Hertz frequency? Click here to see my recommendations: Buying a Hertz enabled Digital Multimeter).

3. Connect the RED lead of the Multimeter to the wire labeled with thenumber1 of the Distributor’s 6 wire connector with an appropriate tool.


4. The Multimeter’s BLACK lead goes to the Battery’s Negative terminal.5. Once everything is set up, have your helper crank the engine while you

observe the Multimeter.6. If the Nissan’s Fuel Injection Computer is feeding the Triggering Signal, you

Multimeter will register around 6 to 8 Hertz (Hz) on its display screen.

CASE 1: If the Multimeter registered 6 to 8 Hertz (Hz), this confirms that the Power Transistor is fried and needs to be replaced. Replacing it will solve your No Spark - No Start problem. Now, at the time of this writing the only way to buy a Power Transistor is to buy the whole distributor.

CASE 2: If the Multimeter DID NOT register 6 to 8 Hertz (Hz), recheck all of yourconnections. If still the Multimeter does not register the indicated Hertz values, this indicates one of three things (as the possible causes of this missing signal): 1) A BAD Crankshaft Position Sensor or 2) an open in this circuit between the Power Transistor and the PCM or 3) a BAD PCM, although this is rare.

TEST 8: Other Causes of a Misfire

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So you’ve done all of the Spark Tests, and still your Nissan pick up (or mini-van, or SUV) is still running rough (rough idle) and/or the Misfiring. Well, here are a couple of suggestions that might help...

1. The Valve Cover Gaskets are leaking oil onto the Spark Plug Wells and soaking the Spark Plugs and Spark Plug Wire Boots in oil.

Over time, this oil will cause a Misfire as the oil cooks and turns into Carbon Tracks.

The photos in the image viewer show you what a Carbon Track looks like on the inside of the Spark Plug Wire Boot and on the ceramic insulator of the Spark Plug.

2. Engine Compression Test One of the most overlooked diagnostic tests to find the root

cause of Misfire is the compression test. You’ll need a Engine Compression Tester of course. The engine Compression readings between cylinders should

not vary more 15%.3. Carbon Tracks on the Spark Plug(s) and in the inside of the Spark Plug

Wires. The photos in the image viewer point (the orange arrows) to

what Carbon Tracks look like. Replace the components as affected with Carbon Tracks.

4. Broken Spark Plugs. This usually happens at tune-up time, if you have dropped

one on the floor. You power washed the engine... this is something that

should never be done on any Nissan vehicle.

How to Test Engine Compression(Nissan 3.0L, 3.3L, 3.5L)

August 19, 2012

Updated: February 06, 2013

Written by: Abraham Torres-Arredondo

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A Compression Test can help you to nail down a hard to find Misfire Condition, since it's one of the most overlooked tests when diagnosing a Rough Idle or MisfireCondition.

The Compression Test will also let you know just how healthy (mechanically) the engine is on your Nissan 3.0L, 3.3L, 3.5L car, pick up, SUV or mini-van.

This article will walk you thru’ the Engine Compression Test and more importantly, I'll show you how to interpret the results of your Compression Test.

Here are the contents of this article at a quick glance:

The ‘Dry’ Engine Compression Test. Interpreting the Results of the Engine Compression Test. The ‘Wet’ Engine Compression Test. Why an Engine Compression Test? Which compression tester Should I Buy? Related Test Articles.

The ‘Dry’ Engine Compression Test

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If your Nissan vehicle starts and runs, it's important to keep in mind that the EngineCompression Test should be done with the engine slightly warmed up.

If your vehicle doesn't run, then don't worry about doing this test with the engine cold.

One last thing, this test is done with the engine cranking... so be carefull and take all necessary safety precautions, your safety is your responsibility

OK, let's get started:

1.1It’s important the engine be slightly warmed up for this test, yet it can not be hot (technically: normal operating temperature) So, if the engine is completely cold, start her up and let it idle for no more than 15 minutes. If the engine has been running fora long period of time, let her cool down for about 1 hour.

2.2Disable the Ignition System.

If your vehicle has a Distributor, you can easily accomplish this by disconnecting all of the Distributor's electrical connectors.

If your vehicle does not have a Distributor (equipped with 6 Coil-on-Plug Ignition Coils), then you'll disable the Ignition System when you remove then in the next step.

3.3Remove all of the six spark plugs. Be careful and don’t drop any of the spark plugs. Dropping them could cause their ceramic insulator to break... and this will cause a Misfire.

Important: If necessary (on Distributor equipped vehicles), tag each spark plug wire before you disconnect them from the spark plugs... so that you'll know where they go when you re-install them.

4.4Hand-thread the engine compression gauge into the spark plughole that you’ve chosen to test first. Do not use any type of toolto get it tight, hand tight is enough!

5.5Once everything is set, have your helper crank the car or mini-van till the needle on the compression tester Gauge stops climbing. It normally takes about 10 seconds or engine cranking to get to this point. When the needle stops moving, you have reached the maximum compression pressure of that cylinder.

6.6Record the reading on a piece of paper along with the cylinder the reading belongs to. Now, repeat this exact same test on theremaining engine cylinders. The illustration in the image viewerwill help you to identify what cylinders you’re testing.

7.7Now, look at all of the four Compression readings that you just wrote down. They should be within 15% of each other. Now, if you don’t understand this 15% part, don’t worry, the next part ofthis article will show you how to interpret what you have just done.

Interpreting the Results of the Engine Compression Test.

Now, I’m gonna’ show you how to interpret all those Compression pressure values you wrote down for each specific Engine cylinder. Here’s what you need to do with them:

1.1

Grab a calculator and multiply the highest compression readingrecorded by .15 (.15 is the decimal equivalent of 15%). So let’s say, for the sake of this example, that the highest reading was 165 PSI (Pounds per Square Inch). Multiplying 165 by .15 gives us 25 (24.75 rounded off).

2.2Subtract 25 from the highest reading. In my example, the highest compression reading is 165... so subtracting 25 from this reading, I get: 140.

3.3So then, 140 PSI is the lowest possible compression reading that any one of the rest of the engine cylinders can have. Any compression reading below this.. and that engine cylinder will misfire.

Let me give you another, but more specific, example: Let’s say that my 2002 Nissan 3.3L Frontier (or Nissan Quest, Pathfinder or whatever), produced the following compression readings:

Cylinder #1 = 165 PSI Cylinder #2 = 85 PSI Cylinder #3 = 145 PSI Cylinder #4 = 160 PSI Cylinder #5 = 170 PSI Cylinder #6 = 165 PSI

The next step would be to apply the formula above and I get 145 PSI as the lowest possible reading (170 x .15= 25, 170-25= 145). So, now I know that cylinder #2 is the one causing the Misfire!!

How to Test Engine Compression(Nissan 3.0L, 3.3L, 3.5L)

August 19, 2012





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The ‘Wet’ Engine Compression Test

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The next step, after finding out that you do have one or more cylinders with low compression, is to add about 2 tablespoons of oil to them... and then retest their compression once more.

The Oil that you're gonna' add to the cylinder will help determine if the low cylinder pressure or pressures you recorded in the ‘Dry’ Compression Test are caused by worn piston rings or worn cylinder Head Valves.

Depending on whether the compression pressure rises (on your compression tester) or not, you'll be able to say that the problem lies in the Piston's rings or in the cylinder head valves.

This test... in which you add engine oil to the cylinders, is known as a ‘Wet’ Compression Test.

OK, this is what you need to do:

1.1Add a small amount of engine oil to the cylinder that reported low compression or no compression in the ‘Dry’ Compression Test.

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The amount should be about 1 to 2 tablespoons of oil.

2.2Install the compression tester onto the cylinder.

Do not use any type of tool to tightened the compression tester... hand tight is fine.

3.3When all is set up, have your helper crank the engine.

4.4You'll get one of two results, either the compression value will go up (from the one you recorded before) or it will stay the same.

CASE 1: The Compression value shot up.. This tells you that the Piston Compression Rings are worn out and thus the problem is in the bottom end (block) of the engine in your 3.0L, 3.3L, or 3.5L Nissan.

CASE 2: The Compression Value stayed the same.. This confirms that the problem is in the cylinder head valves.

Why an Engine Compression Test?

An Engine Compression Test is one of the most important tests to perform when trying to solve a hard to diagnose Misfire Condition / Rough Idle Condition. If only one cylinder has below average compression (compared to the other 5 cylinders), that cylinder will not contribute to engine power... and you’re gonna’ feel it.

Also, no matter what you replace, the Misfire Condition or Misfire Codes (P0300, P0301, P0302, P303, P0304, P0305, P0306) will not go away! Unfortunately, the engine Compression Test is one of the most overlooked Misfire troubleshooting tests. Now, testing the compression of each cylinder is usually done after verifying that each cylinder is getting Spark (this can be easily accomplished by using a Spark Tester).

Which compression tester Should I Buy?

There are lot of engine compression testers to choose from and many places to buy them. I’m gonna’ make two recommendations to you:

1) Which one to buy: The engine compression tester that I have always used is theActron CP7827 compression tester KitMy only complaint about this engine compression tester is that it does not come with a case to store it in.

Engine Compression Gauge Testers

2) Where to buy: You can go down to your neighborhood Auto Parts Store to buy an engine compression tester, but you’ll pay a whole lot more (usually double) thanwhat you can buy it for from the ads that appear in the blue box above.

How to Troubleshoot a No Start (Nissan 3.0L, 3.3L, 3.5L)

January 20, 2013

Updated: October 12, 2013


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What stinks about having your Nissan crank but not start, is that sooo many things can cause it. For example, the no start could be caused by a bad fuel pump,or a blown head gasket, or a busted timing belt, and unfortunately the list goes on.

In this tutorial, which is a primer on what can cause a cranks but does not start condition, I'll share some insights and tips, based from my actual experience, that will help you narrow down your troubleshooting efforts. Whether you Nissan V-6 is front wheel drive (FWD) or rear wheel drive (RWD) or a 4X4... the testing tips and suggestions will apply!


Difference Between a No Start and a No Crank Condition. No Start Condition Basics. No Start 1: Checking for Spark. No Start 2: Checking for Fuel. No Start 3: Checking Engine Mechanical Condition. No Start Summary. Related Test Articles.

Difference Between a No Start and a No Crank Condition

Since all of the articles I write are geared toward the Do-It-Yourself’er (DIY’er)... I want to clarify that a No Crank and a No Start Condition are not the same thing.

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Here's a brief description that'll help you make sense of this tutorial (and will help you find even more info online):

Cranks but Does Not Start Condition: Means that your Nissan's starter motor is cranking the engine but the engine is not starting. This is usually due to a fault in the ignition system, or in the fuel system, or there's an engine mechanical problem (like a thrown rod, etc.).

Does Not Crank Condition: Means that the engine is not cranking when you turn the key to crank the engine. In other words, the engine doesn't turn over at all. Thisis usually due to a bad starter motor, bad ignition switch, bad neutral safety switch, or the engine is locked up.

If your Nissan doesn't crank and you suspect the starter motor, here's a tutorial that'll help you test it: How to Test the Starter Motor (Nissan 3.0L, 3.3L).

No Start Condition Basics

OK, to start opening up about the most basic (and the most important) information you need to know to successfully diagnose the ‘cranks but does not start’ condition of your Nissan... is that the engine needs 3 things to start and run. These are:

1. Air.2. fuel.3. spark.

When your Nissan Cranks but Does Not Start...it's because one of these 3 things is missing from the mix. It's as simple as this! I know, I know... I may be over-simplifying it all... but knowing that only one of three things is missing really helps to put the problem into perspective!

Now, knowing this means that when your or my Nissan doesn't want to start... my job (or your job if you're the one diagnosing/troubleshooting the problem) is to find out which of these 3 things is missing.

To get down into the nitty-gritty details- this means that troubleshooting the problemrequires that you or I check for Spark (with a spark tester), check fuel pressure, and if necessary, check the engine's health with a compression test.

I'll go into more specific details in the following headings:

1.) Ignition System

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The Ignition System is the one tasked with creating and delivering spark to each of the 6 cylinders. Without spark, the engine will crank but Not Start.

The Ignition System of the Nissan vehicles covered by this article use eitherdistributor type system or a COP (Coil-on-Plug) ignition coil system. In a COP ignition coil system, each cylinder has its own ignition coil; thus eliminating the distributor entirely.

In my experience, the most common component failures, of the Ignition System that cause a No Start No spark Condition are:

o Ignition control module (ICM) -most commonly known as theigniter (if distributor equipped).

o Ignition coil.o Distributor cap (if distributor equipped).o Distributor rotor (if distributor equipped).

All of the above Ignition System components can be tested in a methodical way to find out exactly what has failed (if indeed something has).

2.) Fuel System

The Fuel System is the one responsible with supplying the engine with fuel. The Fuel System component that causes the majority of No Start No Fuel

problems:o Fuel pump relay.o Fuel pump.

The fuel pump can be tested to make sure it has really fried using a fuel pressure gauge.

3.) Engine Mechanical System

The components that are responsible for drawing in the air the engine needs are the: engine pistons, cylinder head valves, and all the other related components like: timing chain, etc.

Although rare, internal engine mechanical problems can and do cause No Start Conditions.

Possible internal/external engine problems are:o Blown head gasket.o Blown engine.o Busted timing belt.

OK, the list of possible things that can go wrong looks pretty long... but it is rare to see (or have) two different components go BAD from two separate systems at the same time.

The cool thing is, is that there is a diagnostic strategy that you can use to figure outexactly what's wrong with your particular No Start problem. Let's find out more about it in the next subheading...

No Start 1: Checking for Spark

If your Nissan is suffering a cranks but does not start condition, my suggestion toyou is to start by checking the ignition system. Specifically, what this means is that you should check that all cylinders are getting spark.

Testing for Spark can very easily and safely be done with a dedicated spark tester.

My suggestion, about testing for spark, applies whether your Nissan has a distributor-type ignition system or the more modern COP ignition coil system (in theCoil-on-Plug (COP) ignition coil system, you don't have a distributor anymore but 6 individual ignition coils sitting right on top of the spark plug).

If the Ignition System is the cause of the No Start, you're not gonna' see spark at any of the 6 spark plug wires or 6 COP ignition coils. If there is spark being fed to all cylinders... then you can eliminate the ignition system as the cause of the No Start condition and can move on to other tests (like testing fuel pressure).

Remember, the idea behind checking for spark is to see if all of the engine cylinders are getting spark. Here are the most common causes of a No Spark result:

CASE 1: Spark was present in all cylinders This result tells you three very important things: 1.) the crank sensor is functioning correctly, 2.) the ignition controlmodule (also known as the igniter or power transistor) is OK -this applies to distributor-type systems, and 3.) the ignition coil is good. You don't have to spend any time testing them or any money replacing them.

Your next step is to verify fuel pressure. Go to No Start 2: Checking Fuel.

CASE 2: Spark was NOT present in all of the cylinders (DISTRIBUTOR TYPE):This test result tells you without a doubt that the No Start Condition of your Nissan is due to a malfunction in the Ignition System.

Now, with no spark in any of the engine cylinders, this what I would suggest:

1. Check for spark directly on the ignition coil tower using a spark tester. This is the best way to test the distributor cap. The

distributor cap and rotor are infamous for causing No Spark No Start Conditions.

If you do get spark coming out of the ignition coil tower, you now know beyond a shadow of a doubt the distributor cap and rotor must be replaced.


2. Test the ignition coil and ignition control module (also known as the: igniter or power transistor).

If no spark is firing from the ignition coil, then the next step isto verify that the ignition control (igniter) is activating it. This is a pretty simple test.

3. The following tutorial will give you some specific testing tips: Power Transistor Test & Ignition Coil Test 3.3L Nissan (1996-2004) (at:easyautodiagnostics.com).

CASE 3: Spark was NOT present in all of the cylinders (COP IGNITION COIL TYPE)This test result tells you without a doubt that the No Start Condition of your Nissan is due to a malfunction in the Ignition System.

It's almost impossible for all 6 COP ignition coils to fail at the exact same time... so the most likely cause for this No Spark condition is a BAD crankshaft position sensor.

No Start 2: Checking for Fuel

Checking that the fuel pump is delivering fuel to the fuel injectors is not that hard on your Nissan (since you're able to tap into the rubber fuel pressure hose that connects to the fuel injector rail with a fuel pressure gauge and its appropriate adapter).

A BAD fuel pump will cause your Nissan to Crank but Not Start... since the fuel pump is the one responsible for supplying fuel to the fuel injectors.

The absolute best way to test the fuel pump is with a fuel pressure gauge... using any other method is not as accurate. Still, the other method that I've used to test for a lack of fuel... is spraying starting fluid into the throttle body and then having a helper crank the engine. If the engine starts... then I now know that I need to take acloser look at the fuel pump to see if it's fried or not.

When testing the fuel pump (with a fuel pressure gauge), you'll usually see one of two results:

CASE 1: Fuel pressure is at specification. Not only does this result tell you that the fuel pump is OK but that the following components, that supply the fuel pump with power, are OK too:

Fuel pump fuse. Fuel pump relay.




And so, there's no need to spend time testing them or money replacing them.

CASE 2: Fuel pressure is not present. This usually means that the Pump has failed, but not always. I would recommend testing/checking the following before condemning the fuel pump:

1. After verifying that no fuel pressure exists, check that the fuel pump is getting power by tapping into the power circuit that feeds the pump with 12 volts with a multimeter.

2. Once you're tapped in, have a helper crank the engine while you observe your multimeter in Volts DC mode. If Voltage is present (12 Volts), then youhave confirmed that the fuel pump fuse and fuel pump relay are working perfectly.

3. Confirming power to the fuel pump (with a multimeter) also verifies that the fuel pump has failed and needs to be replaced.

4. If no Voltage is present, as your helper cranks the engine, then the cause ofNo Fuel Condition is due to either a BAD fuse, fuel pump relay (known as the Main Relay).

No Start 3: Checking Engine Mechanical Condition

One of the most overlooked areas, when testing a hard to diagnose No Start, is themechanical condition of your 3.0L, 3.3L, 3.5L Nissan vehicle.

Checking the engine mechanical condition usually means making sure that the timing belt hasn't broken (if equipped with a timing belt). Also, you may need to do: an engine compression test, a blown head gasket test, among a few tests to make sure that an internal engine problem is not the root cause of the cranks but does not start condition your vehicle is experiencing.

Here are some specific tips:

1. When performing an engine compression test, what you're looking for is an average compression reading of NO LESS THAN 120 PSI across all or the majority of the engine cylinders.

2. If you have one or just two readings that are under 90 PSI your Nissan vehicle will still start and run, albeit with a Misfire Condition.

3. The following tutorial will help you do a compression test: How to Test Engine Compression (Nissan 3.0L, 3.3L, 3.5L).

4. NOTE: A broken timing belt will cause all 6 cylinders to output 0 PSI compression.

How to Troubleshoot a No Start (Nissan 3.0L, 3.3L, 3.5L)




January 20, 2013

Updated: October 12, 2013


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No Start Summary

By this point, in this tutorial, you now know that the cranks but does not start condition of your 3.0L, 3.3L, or 3.5L equipped Nissan is due to a lack of one of the following:

1. Spark.2. Fuel.3. Air (from a lack of cylinder compression).

Also, that you can verify if these things are missing or not... which means that you can: test for spark,... you can test the fuel pump (fuel pressure), ... and you can testthe engine compression.

Thankfully, all of these things can be tested with simple tools... which leads me to the next talking point...

...To check the basics, you need tools. There's just no way around it. One of the analogies that I've always enjoyed repeating, about doing a job without the right tools is like trying to eat a bowl of soup with a fork.

So besides knowing what to test, you need tools to do those tests. You don't have to spend an arm and a leg, since you can buy a lot of diagnostics tools that are tailored for the pocket-books of the serious do-it-yourself-er. Here are some of the basic tools you'll need:

Fuel pressure gauge. Spark tester. Compression gauge. Multimeter.

Most of these tools you can buy or rent for free (after you leave a cash deposit which you'll get back when you return the tool) at your local auto parts store




(mainly AutoZone and O'Reilly Auto Parts). Or, if you want to save some bucks, you can buy them online.

Related Test Articles

You can find a complete list of articles here: Nissan 3.0L, 3.3L, 3.5L Index of Articles. Below, is a sample of articles you'll find in this index of articles:

How to Test the Starter Motor (Nissan 3.0L, 3.3L). How to Test Engine Compression (Nissan 3.0L, 3.3L, 3.5L). Power Transistor Test & Ignition Coil Test 3.3L Nissan (1996-

2004) (at:easyautodiagnostics.com).

How to Test the Starter Motor(Nissan 3.0L, 3.3L)

December 28, 2012



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The starter motor can be tested on your 3.0L, 3.3L V-6 equipped Nissan Pathfinder(D21, Pick Up, or QX4) with some very simple tools to see if it's BAD or not.

In this tutorial I'll show you how test the starter motor in a step-by-step way. All the tests are explained in plain English and are accomplished with basic tools.


Important Safety Precautions. Symptoms of a BAD Starter Motor. Tools Needed to Test the Starter Motor. STARTER TEST 1: Applying 12 Volts to the Starter Motor S Terminal. STARTER TEST 2: Verifying the Start Signal. STARTER TEST 3: Voltage Drop Testing the Battery (+) Cable. Related Test Articles.

Important Safety Precautions

Suggestion 1: This is an On-Car Test of the starter motor on your 3.0L or 3.3L Nissan Pathfinder... so you don't need to remove it to test it. The photos I'm using show it off of the vehicle just to make it easier to show you where to make your connections.

http://troubleshootmyvehicle.com/nissan/3.0L-3.3L-3.5L/how-to-test-the-starter-motor-3#4

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Suggestion 2: It's important that the battery in your Nissan be fully charged to perform all of the tests. Also, the battery cable terminals and battery posts must be clean and corrosion free.

Suggestion 3: Use jack stands to keep your Nissan Pathfinder (D21, Pick Up, or QX4) up in the air... don't trust the jack alone! Take all necessary safety precautions, like using jack stands to hold up the vehicle, wearing eye-protection (safety glasses), etc.

Suggestion 4: If your vehicle has a standard transmission... make sure that it's outof gear and in neutral, and the parking brake is activated/on.

Symptoms of a BAD Starter Motor

When the starter motor goes BAD on your 3.0L, 3.3L Nissan Pathfinder (D21, Pick Up, or QX4), you'll see one of the following symptoms:

1. Then engine doesn't turn over (crank) when you turn the key to start the engine.

2. A jump start does not help. The vehicle’s engine still refuses to crank.3. The battery has been charged and/or replaced and still your Nissan does

not crank.4. When you turn the key to crank the engine, all you hear is a small knock

and nothing else.

Although the above list is a not a very complete list of symptoms... the theme that runs thru’ them, and any other related symptom, is that the engine will not turn overwhen you try to start it.

Tools Needed to Test the Starter Motor

You don't need expensive test equipment to test the starter motor on your 3.0L, 3.3L 6 cyl. Nissan Pathfinder... but you do need a few things. These are:

1. Jack.2. Jack stands.3. Remote starter switch.

If you'd like to see what a remote starter switch looks like, you can follow this link: Actron CP7853 Remote Starter Switch.

You can either buy this tool online or you can buy it at your local auto parts store (AutoZone, O'Reilly, Pepboys, etc.).

4. Multimeter or a 12 Volt automotive test light.

http://www.amazon.com/gp/product/B0009XQUKW/ref=as_li_tf_tl?ie=UTF8&tag=easyautodiagn-20&linkCode=as2&camp=1789&creative=9325&creativeASIN=B0009XQUKW

http://www.amazon.com/gp/product/B0009XQUKW/ref=as_li_tf_tl?ie=UTF8&tag=easyautodiagn-20&linkCode=as2&camp=1789&creative=9325&creativeASIN=B0009XQUKW

If you don't have a Multimeter or need to upgrade yours, check out my recommendation here: Abe's Multimeter Recommendation (at: easyautodiagnostics.com).

5. A wire piercing probe. This tool is not an ‘absolute must have tool’ but I can tell you

from experience that it makes it a whole lot easier to probe the S terminal wire for the Start Signal.

If you'd like to see what this tool looks like, you find out moreabout it here: Wire Piercing Probe Tool Review (Power Probe PWPPPPP01).

6. A helper.

As you can see... you don't need anything expensive. OK, let's turn the page and get starter with the first starter motor test.

STARTER TEST 1: Applying 12 Volts to the Starter Motor S Terminal

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This first starter motor test will let you know right away if the starter motor is fried ornot.

What we're gonna' do is to simply apply 12 volts to the starter motor solenoid S terminal using a remote starter switch.

NOTE: Getting to the starter motor solenoid S terminal (to manually apply 12 volts)can be quite a challenge... but not impossible. What I do is use a wire piercing probe to pierce the S terminal wire and then I connect my remote starter switch to itand proceed from there... I suggest you do the same (to see what this tool looks like, go here: Wire Piercing Probe Tool Review (Power Probe PWPPPPP01)).

OK, this is what you'll need to do:

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1.1Jack up your Pathfinder (D21, Pick Up, or QX4) and place on it jack stands. Remember, to only way to gain access to the starter motor is from underneath your Pathfinder.

2.2Disconnect the battery negative terminal.

You'll reconnect it back in one of the following steps, for now, it's a safety precaution as you set up the test.

1.3Attach a remote starter switch to the S terminal of the starter motor solenoid.

This is easier said than done... so take your time and make sure the connection is on the S terminal of the starter motor solenoid.

Also, in case you're wondering... you can leave the starter motor solenoid's S terminal wire connected to the engine's wiring harness connector or not, the test will work either way.

2.4Reconnect the negative battery cable to the battery negative post.

Now, apply 12 volts to the S terminal wire of the starter motor starter solenoid with your remote starter switch. As you apply these 12 Volts (to the S terminal wire of the starter motor solenoid), you'll get one of two results:

The starter will activate and will turn over the engine -OR- The starter motor won't do a thing.

Let's take a look at what your test results mean:

CASE 1: The starter motor cranked the engine. This test result let's you know that the starter motor is OK and functioning. It also tells you that the probable cause, of it not working when you turn the key to start the engine, is a lack of the 12 Volt Start signal on the S terminal of the starter motor solenoid.

The next step is to go to TEST 2 and see if the starter motor is getting the 12 Volt Start signal on the S terminal wire (circuit). Go to TEST 2: Verifying the Start Signal.

CASE 2: The starter motor DID NOT crank the engine. This usually means that your starter motor is BAD and needs to be rebuilt or replaced.

I suggest 2 more tests and these are make sure that the starter motor is getting its 12 Volt Start signal and to test the battery cable (that attaches to the starter motor starter motor) for corrosion. This can be accomplished very easily with a voltage drop test.

Go to: TEST 2: Verifying the Start Signal. Go to: TEST 3: Voltage Drop Testing the Battery Cable.

STARTER TEST 2: Verifying the Start Signal

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As you may already know, when you turn the key to crank/start the engine... the starter motor gets 12 Volts on the S terminal wire of the starter motor solenoid. These 12 Volts are known as the Start signal.





So, in this test step, we're gonna' see if the starter motor solenoid is getting this Start signal on the S terminal wire. Since you already have your vehicle up on jack stands... this test won't be that hard to do.

You can use a multimeter or a 12 Volt automotive test light. Ok, here’s what you’ll need to do:

1.1Lift the vehicle and place it on jack stands (if it isn't already up in the air). Now, while underneath the vehicle, connect the REDmultimeter lead to the S terminal wire of the starter motor.

The S terminal wire, of the starter solenoid, must remain connected to it's engine wiring harness connector for this test to work.

2.2Attach the BLACK multimeter lead to a clean and rust-free spoton the engine or on the vehicle frame.

Here I’m going to recommend something to you: Use a battery jump start cable to ground the BLACK multimeter lead to a clean ground point on the engine. The reason why is that depending on how rusty and dirty the underneath of the vehicle... you may NOT be able to find a clean and rust-free spot to ground the multimeter’s BLACK lead.

3.3Now, have your helper hop inside the vehicle and turn the key to crank the engine.

The engine won’t turn over, but the idea is to verify that the starter motor solenoid is getting the 12 Volt start signal from theIgnition Switch.

4.4

Your multimeter is going to register one of two results: Either 10 to 12 Volts DC or no voltage at all.

Alright, let’s interpret the results of this test...

OK, let’s make sense of the readings that your multimeter recorded in the test:

CASE 1: If your multimeter registered 10 to 12 Volts: This test result let’s you know the starter solenoid is receiving the Start signal (crank signal).

This means that we can forget about the Safety Neutral Switch and the Ignition Switch being BAD. OK, now the next test is to do a very easy and simple voltage drop test. Go to TEST 3.

CASE 2: If your multimeter DID NOT register 10 to 12 Volts: This result exonerates the starter motor. Your starter motor is not BAD.

Here’s the reason why... without this 10 to 12 Volt Crank Signal, the starter motor will not crank the engine. Now, although it’s beyond the scope of this article to test the Neutral Safety Switch or the Ignition Switch, you have eliminated the starter motor and this means saving money by not buying a part your vehicle does not need.

STARTER TEST 3:Voltage Drop Testing the Battery (+) Cable

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Although you've probably already cleaned the battery cable terminals and the battery posts of corrosion... there's still a good chance that hidden corrosion (on


the battery positive cable) is blocking battery power from reaching the starter motor(this condition is known as a voltage drop).

The absolute best way to eliminate this possibility, is with a simple voltage drop testof the battery positive cable that attaches to the large stud of the starter motor solenoid.

To further explain what a voltage drop is: a voltage drop is simply a condition in which unseen corrosion blocks a lot of the battery power from reaching the starter motor. When this happens, the starter motor will not be able to crank the engine in your Nissan 3.0L, 3.3L Pathfinder (D21, Pick Up, or QX4), even though the battery is in a fully charged state.

OK, to get started, this is what you need to do:

1.1Place you multimeter in Volts DC mode. Attach the RED multimeter lead to the center of the positive battery terminal. If the positive battery post isn’t clean... clean a spot right on the top of it. It’s important that the multimeter lead make contact right in the center of the positive battery post.

You may need two helpers for this test step, since someone willhave to hold the RED multimeter lead onto the battery positive terminal and someone else will need to crank the vehicle while you perform the next step.

2.2With the BLACK multimeter lead, touch the center of the startersolenoid stud to which the big battery cable attaches to. You’ll maintain the BLACK multimeter lead in this position throughoutthe next step.

3.3Now, have a helper turn the key to crank the engine from insidethe vehicle. This is important, since a voltage drop test has to

be done while the component in question is working (or trying to work).

4.4OK, if all is good (no voltage drop), your multimeter will register0 Volts (.5 volts is still 0 Volts). If there’s a voltage drop, your multimeter will register Voltage (usually above 7 Volts DC.)

OK, now that the testing part is done... let’s take a look at what your results mean:

CASE 1: Your multimeter registered 0 Volts (no voltage drop): This result indicates that the starter motor is receiving all of the battery Voltage and Amperageit needs to crank the vehicle.

This also means that the starter motor is BAD, and here’s why:

1. In STARTER TEST 1 you confirmed that the starter motor doesn't work when you apply power to the S terminal wire of the starter motor solenoid.

2. STARTER TEST 2 you confirmed that the starter motor is receiving the Crank Signal.

3. In this test step you have confirmed that no voltage drop exists on the battery positive Cable.

These 3 test results, taken together, indicate that the starter motor is BAD. Replacing the starter motor should solve your No Crank Condition.

I’m going to make two more recommendations to you. 1.) Before removing the starter motor, manually turn the engine using a 1/2 ratchet and the appropriate socket.. just to make sure the engine or the A/C Compressor have not locked up and causing the No Crank Condition and 2.) Bench Test the starter motor after removing it. This is a super easy test to do and you can find this article by clicking here: Bench Testing the Starter Motor (at: easyautodiagnostics.com).

CASE 2: Your multimeter registered 5 Volts or more: This result tells you that a voltage drop does exist and this is not a good result.

The good news is that this can easily be corrected, since a voltage drop is always caused by some sort of corrosion issue on the battery positive Cable or terminals or the battery positive post.

http://easyautodiagnostics.com/starter_motor_test/starter_bench_test_1.php

The solution is to thoroughly clean the battery positive post and the battery positiveterminal (both the end that attaches to the battery positive post and the end the connects to the starter motor solenoid).

After cleaning, try cranking the engine. If it cranks and starts, no further testing is required.

Related Test Articles

You'll find a complete list of Nissan 3.0L, 3.3L tutorials in the following index: Nissan 3.0L, 3.3L Index of Articles.

Here's a small sample of the articles/tutorials you'll find in the index:

Power Transistor Test & Ignition Coil Test Nissan 3.3L (1996-2004) (at:easyautodiagnostics.com).

Engine Compression Test Nissan 3.0L, 3.3L, 3.5L. How to Test Engine Compression (Nissan 3.0L, 3.3L). Mass Air Flow (MAF) Sensor Test 3.3L Frontier, Quest, Pathfinder,

XTerra(at: easyautodiagnostics.com).

How to Test the MAP Sensor P0105(3.3L Nissan Pathfinder)

August 20, 2013

Updated: August 23, 2013


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Testing the MAP sensor (and the resulting P0105 code) on your Nissan Pathfinder isn’t hard and in this tutorial I’ll show you how to.

You don’t need any expensive testing equipment. You don’t even need a scan tool. All you need is a multimeter.

Here are the main points of this tutorial at a quick glance:

MAP Sensor Circuit Descriptions. Before You Start the MAP Sensor Test. TEST 1: Checking for the MAP Sensor Signal. TEST 2: Checking that MAP Sensor is Getting Power. TEST 3: Verifying the MAP Sensor is Getting Ground.

MAP Sensor Circuit Descriptions

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Image 1 of 2

As you’re already aware, the MAP sensor on your Nissan Pathfinder has 3 wires coming out of its harness connector.

These wires (circuits) are tasked with feeding power and ground and taking the MAP signal back to the PCM.

All of the tests in this tutorial are done to the harness connector. In the image viewer you’ll see the pin outs for the MAP sensor itself and its harness connector.

Nissan Pathfinder MAP Sensor Pin Out

Pin Description

1 Sensor Ground

2 MAP Sensor Signal

3 5 Volt Reference

Before You Start the MAP Sensor Test

Before you start the MAP sensor test on your Nissan Pathfinder (Frontier or QX4), you need to make sure that the sensor is getting vacuum (after the engine has started).

If the MAP sensor is not getting vacuum... then the most likely culprit is the MAP/BARO switch solenoid valve that is defective (since this solenoid valve is the one that provides the MAP sensor with vacuum) or misrouted vacuum hoses.

For more information take a look at the following tutorial:

MAP/BARO Pressure Solenoid Test (1996-2004 3.3L Pathfinder).

TEST 1: Checking for the MAP Sensor Signal

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In this first test we’re going to tap into the middle wire of the MAP sensor with a multimeter and see if the map sensor is producing a map signal when we manuallyapply vacuum to it.

You can apply vacuum to the MAP sensor with a vacuum pump or you can use the good ol’ lungs (although using a vacuum pump is the most accurate way of testing the map sensor).

NOTE: Although you’ll be bench testing the MAP sensor of your Nissan Pathfinder... you still need to leave the MAP sensor connected to its harness connector so that it can get both power and ground (to produce a signal).

OK, these are the test steps:

1.1Remove the MAP sensor from its location near the air filterbox (if you need to gain access to its vacuum port).

Once you have removed it, reconnect it back to its harness connector.

2.2Select Volts DC on your multimeter and probe the middle wire of the MAP sensor with the red multimeter lead.

This is the wire that connects to the MAP sensor engine harness connector’s terminal labeled with the number 2 in the image viewer.

The best way to get to the signal inside the wire is using a wire piercing probe (to see what this tool looks like, click here: Wire-Piercing Probe).

3.3Ground the black multimeter lead on the battery’s negative terminal.

4.4Now, connect your vacuum pump to the MAP sensor and turn the Key to the ON position (don't start the engine).

5.5With the key On and no vacuum applied to the MAP sensor your multimeter should display:

3.2 to 4.8V (this is no vacuum applied to the MAP sensor).

Apply Vacuum. As you apply vacuum, your multimeter’s voltagereading should start to decrease. Once you have reached 7.8 in. Hg vacuum, your multimeter should read:

1.0 - 1.4 Volts DC. See photo 3 of 3 in the image viewer above to see these

numbers on the vacuum pump.

NOTE: What you’re looking for, as you apply and release vacuum is for the multimeter to show a decrease in voltage (as you apply vacuum) and an increase in the voltage back to 4.5+ volts (as you release vacuum).

Let’s take a look at what your test results mean:

CASE 1: The MAP sensor’s voltage decreased as you applied vacuum- This tells you that the MAP sensor is OK and not the true cause of the MAP sensor codes.

http://troubleshootmyvehicle.com/Index-of-Tool-Reviews/wire-piercing-probe

This also confirms that your Nissan Pathfinder’s (Frontier, QX4) MAP sensor is getting power (5 Volts) on wire and ground.

CASE 2: The MAP sensor’s voltage DID NOT decrease as you applied vacuum-This usually means that the MAP sensor is BAD... but we'll need to make sure that the MAP sensor is getting both power and ground.

For this test, go to TEST 2: Checking that MAP Sensor is Getting Power.

TEST 2: Checking that MAP Sensor is Getting Power


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If in TEST 1 your Nissan Pathfinder’s MAP sensor did not create a signal... then there's a good chance that the sensor is missing either power or ground.

So the next step is to verify that the MAP sensor is getting 5 volts on terminal number 3 of its harness connector (see illustration in the image viewer).



NOTE: You can check for these 5 volts with the MAP sensor connected or disconnected from its harness connector.

This is what you'll need to do:

1.1Place your multimeter in Volts DC mode and with the red multimeter lead, probe the wire labeled with the number 3.

Avoid probing the front of the connector... to avoid damagingthe female metal terminal.

The best way to get to the Signal inside the wire is using a Wire Piercing Probe (to see what this tool looks like, click here: Wire-Piercing Probe).

2.2Ground the black multimeter lead directly on the battery’s negative terminal.

3.3Turn the key to the ON position (but don't start the engine).If all is OK, your multimeter should read 4.5 to 5 Volts DC.

Let's take a look at your test results:

CASE 1: 4.5 to 5 Volts are present- So far so good, since this means that the PCM is supplying power to the manifold absolute pressure (MAP) sensor.

The next step is to make sure that the PCM is feeding your Nissan’s MAP sensor with ground. For this test, go to TEST 3: Verifying the MAP Sensor is Getting Ground.

CASE 2: 4.5 to 5 Volts ARE NOT present- Recheck your multimeter connections and retest...

... If after checking all of your multimeter connections and making sure the Key is inthe ON position AND your multimeter does not register the 4.5 to 5 Volts DC, then you've found the reason for the MAP sensor code/failure.




Without power in this circuit, the MAP sensor will not work. Now, it's beyond the scope of this article to test for this missing Voltage, but the most likely cause will bean ‘open’ short between the PCM connector and the MAP sensor connector.

TEST 3: Verifying the MAP Sensor is Getting Ground


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So far you’ve verified two important things about your Nissan’s MAP sensor:

One: The MAP sensor is NOT producing a signal (TEST 1).

Two: That it’s getting power on terminal number 3 of the harness connector (TEST2).

The next step is to check that terminal number 1of the sensor’s harness connectoris feeding the MAP sensor ground.

IMPORTANT: The PCM is the one that provides this ground internally, so be careful and don't intentionally or accidentally short this wire to battery voltage or you'll fry the PCM.





1.1Place your multimeter in Volts DC mode and with the black multimeter lead, probe the wire that connects to the terminal labeled with the number 1 of the MAP sensor’s harness connector.

Avoid probing the front of the connector... to avoid damagingthe female metal terminal.

The best way to get to the signal inside the wire is using a Wire Piercing Probe (to see what this tool looks like, click here: Wire-Piercing Probe).

2.2Connect the red multimeter lead directly to the battery’s positive (+) terminal.

3.3Turn the Key to the ON position (but don't start the engine).

If all is OK, your multimeter should read 10 to 12 Volts DC.


CASE 1: Your multimeter showed battery voltage- So far so good, since this means that the PCM is supplying power to the manifold absolute pressure (MAP) sensor.

This confirms that the manifold absolute pressure (MAP) sensor is BAD and needs to be replaced. Why? Well, because so far you have confirmed that:

1. The MAP sensor is not producing a signal when vacuum is applied to it (TEST 1).

2. The MAP sensor is getting its 5 Volts (TEST 2).3. In this test step, you've confirmed that the MAP sensor is getting ground.

Taking all of these 3 test results... you can conclude with confidence that you need to replace the MAP sensor with a new one.




CASE 2: Your multimeter did NOT show battery voltage- Recheck your multimeter connections and retest...

... If after checking all of your multimeter connections and making sure the Key is inthe ON position AND your multimeter does not register the 10 to 12 Volts DC, then you've found the reason for the MAP sensor code/failure.

Without ground in this circuit, the MAP sensor will not work. Now, it's beyond the scope of this article to test for this missing ground, but the most likely cause will be an ‘open’ between the PCM connector and the MAP sensor connector.

Where to Buy the MAP Sensor and Save

The MAP sensor on your Nissan Pathfinder (Frontier, QX4) isn’t cheap. So if the MAP tests confirm that it’s bad and you need to replace it... take a look at the bottom links and do some comparison shopping:

More 3.3LNissan Test Tutorials

You can find a complete list of tutorials here: Index of Nissan 3.0L, 3.3L, 3.5L Articles.

Here’s a sample of the tutorials you’ll find in the index:

MAP/BARO Pressure Solenoid Test (1996-2004 3.3L Pathfinder). P0130, P0150 Front O2 Sensor Tests (1996-2000 3.3L Nissan Pathfinder). Throttle Position Sensor Test (Nissan 3.3L Pathfinder, Xterra, Frontier). How to Troubleshoot a No Start (Nissan 3.0L, 3.3L, 3.5L). How to Test Engine Compression (Nissan 3.0L, 3.3L, 3.5L).

MAP/BARO Pressure Solenoid Test(1996-2004 3.3L Pathfinder)

August 16, 2013







http://troubleshootmyvehicle.com/nissan/3.0L-3.3L-3.5L/throttle-position-sensor-tests-1

http://troubleshootmyvehicle.com/nissan/3.0L-3.3L-3.5L/P0130-and-P0150-diagnostic-tests-1


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Testing the MAP/BARO switch solenoid valve (and the resulting P1105 trouble code) on your Nissan Pathfinder isn’t hard and it’s something you can do yourself.

In this tutorial, I’ll show you what you need to do to find out if it’s bad (or not) in a step-by-step way.

NOTE: Although this tutorial is written with the Nissan 3.3L equipped Pathfinder in mind... it also applies to the 3.5L equipped Pathfinder (QX4) and 3.3L/3.5L Frontier,since the same type of BARO/MAP switch solenoid valve is used on both vehicles. For more specifics, see the ‘Applies To:’ box on the right.

Here’s the content of this tutorial at a quick glance:

MAP/BARO Switch Solenoid Valve Diagnostic Essentials. TEST: Bench Testing the MAP/BARO Switch Solenoid Valve. More Nissan Pathfinder (Frontier, Xterra) Tutorials. Nissan Pathfinder Auto Parts Deals.

MAP/BARO Switch Solenoid Valve Diagnostic Essentials

http://troubleshootmyvehicle.com/nissan/3.0L-3.3L-3.5L/MAP-BARO-solenoid-tests-2#2





http://troubleshootmyvehicle.com/Nissan-3.0L-3.3L-3.5L-Index-of-Articles/map-baro-solenoid-tests.html

What it does: The MAP/BARO switch solenoid valve is tasked with the job of providing manifold vacuum to the MAP sensor a few seconds after the engine starts up. Why?...

... So that the MAP sensor can take a barometric pressure reading before the MAP/BARO switch feeds it intake manifold vacuum.

So, when it doesn’t switch from barometric pressure to manifold vacuum pressure (after your Nissan Pathfinder starts up), your Nissan Pathfinder’s (or Frontier’s) PCM lights up the check engine light and sets a P1105 trouble code and MAP sensor code.

Vacuum hose routing: Using the illustration above, here are the MAP/BARO switch solenoid valve vacuum hose specifics:

Vacuum hose port Ao To air cleaner box.

Vacuum hose port Bo To MAP sensor (called the absolute pressure sensor by

Nissan). Vacuum hose port C

o Manifold vacuum.

Common Problems: The most common causes of a P1105 MAP/BARO switch solenoid valve trouble code are:

Misrouted vacuum hoses. Broken vacuum hoses. Failed MAP/BARO switch solenoid valve.

What you need to do first: Before you start testing the MAP/BARO switch solenoid valve itself... you need to make sure that:

1. All vacuum hoses that connect to the solenoid valve are routed correctly.2. The vacuum hoses that connect to the solenoid valve are not broken or

leaking vacuum.3. The vacuum hose that connects to the vacuum port labeled with the letter

C(in the illustration above) has vacuum with the engine running.4. MAP sensor is getting vacuum a few seconds after the engine starts.

If the MAP sensor is NOT getting vacuum, then proceed to TEST 1.

TEST: Bench Testing theMAP/BARO Switch Solenoid Valve


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Now that you’ve checked that all of the vacuum hoses (that connect to the MAP/BARO switch solenoid valve) are routed correctly, that the switch is being fed vacuum and the MAP sensor is not getting vacuum (after the engine has started)...

... The next step is to bench test the solenoid valve itself to see if it’s fried (or not).

Bench testing the MAP/BARO switch solenoid valve simply involves removing it and applying power and ground to it (with jumper wires). And in this test step I’ll show you how.

Here’s what you need to do:

1.1Remove the MAP/BARO switch solenoid valve, from its location underneath the MAP sensor (see photo 3 of 3 in the image viewer above).

2.2Apply battery voltage to pin 1 and ground to pin 2 of the solenoid valve using jumper cables.

NOTE: Use a fused jumper wire to apply 12 volts from your Nissan Pathfinder’s battery to pin 1.

1. 3

With battery power and ground applied:

Air should now pass between ports A and B. Air should NOT pass between ports B and C.

2.4With battery power and ground removed:

Air should NOT pass between ports A and B. Air should pass between ports B and C.

Let’s take a look at your test results:

CASE 1: Air passed (and not passed) as specified. This test result tells you thatthe MAP/BARO switch solenoid valve is OK and not the cause of the P1105 diagnostic trouble code.

If the P1105 trouble code is still present... then your next step is to check that the two circuits that feed power and the activation signal from the PCM are not shortedto ground or ‘open’. Although this is beyond the scope of this tutorial, you have eliminated the MAP/BARO switch solenoid valve as being defective.

CASE 2: The solenoid valve did not work as specified. This test result tells you that the MAP/BARO solenoid is fried and needs to be replaced with a new one.

More Nissan Pathfinder (Frontier, Xterra) Tutorials

You can find a complete list of tutorials here: Nissan 3.0L, 3.3L, 3.5L Index of Articles.

Here’s a sample of the type of tutorials you’ll find in the index:

P0130, P0150 Front O2 Sensor Tests (1996-2000 3.3L Nissan Pathfinder). How to Test the Idle Switch (Nissan 3.3L Pathfinder, Xterra, Frontier). Throttle Position Sensor Test (Nissan 3.3L Pathfinder, Xterra, Frontier). How to Troubleshoot a No Start (Nissan 3.0L, 3.3L, 3.5L). How to Test Engine Compression (Nissan 3.0L, 3.3L, 3.5L).

Nissan Pathfinder Auto Parts Deals




http://troubleshootmyvehicle.com/nissan/3.0L-3.3L-3.5L/how-to-test-the-idle-switch-1




P0130, P0150 Front O2 Sensor Tests(1996-2000 3.3L Nissan Pathfinder)

August 16, 2013



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In this tutorial I am going to show you how to test diagnostic trouble codes P0130 and P0150 on your 3.3 liter equipped Nissan Pathfinder.

These codes indicate a problem with the front O2 sensors which are the sensors located before the catalytic converter for Bank 1 and Bank 2.

This tutorial applies to the 1997 to 2000 3.3 liter V6 Nissan Pathfinder.

Here are the main points of this tutorial at a quick glance:

P0130 and P0150 Diagnostic Essentials. Diagnosing Trouble Codes P0130 and P0150. TEST 1: Checking Upstream Oxygen Sensor Performance. TEST 2: Manually Inducing a Rich Condition. TEST 3: Checking the Resistance of the O2 Heater Element. TEST 4: Checking the Continuity Between the O2 Sensor and PCM. Where to Buy your Nissan Pathfinder’s O2 Sensors and Save.

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http://troubleshootmyvehicle.com/Nissan-3.0L-3.3L-3.5L-Index-of-Articles/p0130-and-p0150-diagnostic-tests.html



More Test Articles.

P0130 and P0150 Diagnostic Essentials

Usually what causes these two codes to pop up on your Nissan Pathfinder is a failed right (or left) upstream oxygen sensor but not always.

Thankfully, by doing some specific tests, you and I can check to see if they’re bad (or not) before replacing them.

Before we jump into the tests, here’s some specific information about these two codes that will help us understand exactly what they’re trying to tell us:

P0130: O2 Sensor Circuit Malfunction (Bank 1 Sensor 1). This trouble code letsus know that the PCM is detecting that:

The front O2 sensor for Bank 1 is not switching between .2 to .8 volts (as the engine is running).

That the front O2 sensor for Bank 1 is stuck producing an output voltage of .2 - .4 volts DC.

That the fault could lie in the front oxygen sensor itself or in the wiring between the sensor and the fuel injection computer.

NOTE: Bank 1 is the bank that houses cylinders 1, 3, and 5. Bank 1 Sensor 1 is commonly referred to as:

o Right front oxygen sensor.o Upstream right oxygen sensor.o Bank 1 Sensor 1.o O2S11.

P0150: O2 Sensor Circuit Malfunction (Bank 2 Sensor 1):


The front O2 sensor for Bank 2 is not switching between .2 to .8 volts (as the engine is running).

That the front O2 sensor for bank 2 is stuck producing an output voltage of .2 - .4 volts DC.

That the fault could lie in the front oxygen sensor itself or in the wiring between the sensor and the fuel injection computer.

NOTE: Bank 2 is the bank that houses cylinders 2, 4, and 6. Bank 2 Sensor 1 is commonly referred to as:

o Left front oxygen sensor.o Upstream left oxygen sensor.o Bank 2 Sensor 1.o O2S21.

As you can see from the information above... both codes (P0130 and P0150) aren’taccusing either of the two upstream oxygen sensors as having failed... since quite a few things can cause them to stay stuck producing a fixed voltage between .2 - .4volts.

Diagnosing Trouble Codes P0130 and P0150

Getting to the bottom of what’s causing these 2 codes to light up the check engine light (CEL) on your Nissan Pathfinder involves 4 specific tests.

NOTE: Both the right and left upstream oxygen sensors are tested in the exact same way... so all of the tests (in this tutorial) apply to them both.

1. The first test is to confirm that the oxygen sensor’s output isn't the right output.

Go to TEST 1: Checking Upstream Oxygen Sensor Performance.

2. The second test involves creating a rich air fuel mixture and seeing if the right and left upstream O2 sensors react to it.

Go to TEST 2: Manually Inducing a Rich Condition.3. The third test involves measuring the resistance of the internal heater of the

upstream oxygen sensor. Go to TEST 3: Checking the Resistance of the O2 Heater

Element.4. The last test involves testing the continuity of the oxygen sensor’s wires

between its harness connector and the fuel injection computer’s harness connector.

Go to TEST 4: Checking the Continuity Between the O2 Sensor and PCM.

TEST 1: Checking Upstream Oxygen Sensor Performance









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The very first thing that we need to do is check the right (or left) O2 sensor output voltage to see if it’s stuck between .2 to .4 volts DC after the engine has started and warmed up.

This can be very easily accomplished using a scan tool with live data mode.

If you don't have a scan tool don't panic because you can use a multimeter to test for the right (or left) upstream oxygen sensor’s output voltage (and I’ll also include how to do it).

Is you don't have a scan tool and are thinking about buying one or need to upgradeyour code reader, check out my recommendation here: Actron CP9580 Scan Tool Review.

These are the test steps:

1.1

http://troubleshootmyvehicle.com/Index-of-Tool-Reviews/actron-cp9580-scan-tool-review-1

http://troubleshootmyvehicle.com/Index-of-Tool-Reviews/actron-cp9580-scan-tool-review-1

Connect your scan tool, turn the key to the On position, and go to its live data mode.

If you’re using a multimeter: Place the multimeter in volts DC mode, connect the red lead to the wire to the middle wire of theupstream oxygen sensor you’re testing, and ground the black test lead on the battery’s negative terminal.

2.2Start your Pathfinder’s engine and let it warm up.

In the meantime, scroll down to the PID’s labeled: O2S11 and O2S21(see the image in the image viewer).

PID O2S11 represents the output from the right upstream oxygen sensor and PID O2S21 represents the left upstream oxygen sensor.

3.3Once the engine has reached normal operating temperature, PIDO2S11 and O2S21 should show a constant sweeping voltage signal of .2 to .8 volts.

In other words: The voltage should move constantly between .2volts to .8 volts the entire time the engine is running.

If you’re using a multimeter: Your multimeter should register a voltage (for the upstream O2 sensor you’re testing) that’s constantly moving between .2 volts to .8 volts as the engine runs.

CASE 1: The upstream oxygen sensor output voltage constantly moved between .2 to .8 volts. This test results tells you that the oxygen sensor that you’re observing either on your scan tool or with your multimeter is functioning correctly at this point in time.

This test results also tells you that the problem is intermittent since it’s not present at this time.

CASE 2: The upstream oxygen sensor output voltage stayed stuck between .2 to .4 volts. This test result definitely tells you that the upstream O2 sensor you’reobserving on your scan tool or multimeter has a problem.

The next step is to manually induce a rich condition and see if the O2 sensor that you’re observing responds to this rich condition. If it doesn’t respond to it... then weknow that it has failed and needs to be replaced. For this test go to: TEST 2: Manually Inducing a Rich Condition.

TEST 2: Manually Inducing a Rich Condition


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You’ve reached this point because in TEST 1 you confirmed that the right (or left) upstream oxygen sensor is stuck producing a continuous voltage (when it should be alternating between .2 and .8 volts).




The next step is to manually induce a rich condition by spraying carburetor spray into a vacuum hose while the engine runs.

If the right (or left) upstream oxygen sensor on your Nissan Pathfinder is working correctly... as soon as the carb. spray gets burned in the cylinder... its output voltage should hit .8 to 1.0 volt DC.

IMPORTANT: Take all necessary safety precautions since this test requires that you work around a running engine. Stay alert, use common sense, and be careful.

Here are the step-by-step instructions:

1.1Start your Pathfinder’s engine, scroll down to the left and right upstream oxygen sensor PIDs labeled O2S11 and O2S21.

2.2Make sure your Pathfinder’s engine has reached normal operating temperature before you proceed to the next step.

3.3Have a helper spray a little bit of carburetor cleaner into the intake manifold via a small vacuum hose with the engine running and while you observe the scan tool’s upstreamoxygen sensor PIDs.

4.4As soon as the carburetor spray hits the inside of the intake manifold (via the vacuum hose) and enrichens the air/fuel mixture, your scan tool should read 0.800 to 1.0 volt for both O2S11 and O2S21.

You can repeat step 3 several times, if you need to make sure of your test result.


CASE 1: The O2S11 and O2S21 values increased to .8 to 1 V and stay there as long as you were spraying carb spray. This test result confirms that both the left and right oxygen sensors are OK.

CASE 2: The O2S11 and O2S21 values values did not shoot up as the carb spray was being sprayed. This result confirms that there’s a problem with the O2 sensor you’re observing on the scan tool or with the multimeter.

Generally, this means that the O2 sensor you’re observing/testing is bad... I suggest doing the other two tests (in this tutorial) to make sure. For the first (of two), go to TEST 3: Checking the Resistance of the O2 Heater Element.

TEST 3: Checking the Resistance of the O2 Heater Element


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In this test we’re going to check the resistance of the heater element within the right (or left) upstream oxygen sensor.


You don't have to remove the right (or left) upstream O2 sensor from your Nissan Pathfinder to test the resistance of a heater element... since its connector is easily accessible from the engine compartment.

Since the Nissan factory resistance specifications (for the heater element) calls for the right (or left) upstream sensor to be at room temperature (77 °F (25 °C)), you’regoing to have to perform this test with a completely cold engine.

NOTE: The illustration in the image viewer applies to both the left and right upstream oxygen sensors on your Nissan Pathfinder.

These are the test steps:

1.1With the key in the Off position, disconnect the oxygen sensor that you’re gonna’ test.

NOTE: The engine (and thus the O2 sensor) has to be completely at room temperature.

2.2Measure the resistance between terminals 1 and 3 of the upstream oxygen sensor you’re testing (use the illustration inthe image viewer above to identify the correct O2 sensor terminals).

The resistance between these two outer terminals of the upstream oxygen sensor should be between 2.3 to 4.3 Ohms (Ω) at 77 °F (25 °C) if all is OK (with the heater element).

3.3Check for continuity between terminals 1 and 2 and check for continuity between terminals 2 and 3. If the upstream sensor is OK, there should NOT be any continuity between these terminals.


CASE 1: The upstream O2 sensor heater element’s resistance is within specification and there’s no continuity between terminal 1 and 2 and betweenterminal 2 and 3. This is the correct and expected test result and tells you that the internal heater element of the upstream oxygen sensor you’re testing is OK.

So far you have:

1. Confirmed that the right (or left) upstream O2 sensor is stuck producing a continuous voltage in TEST 1.

2. Confirmed that the right (or left) upstream O2 sensor does NOT react to a manually induced rich condition TEST 2.

3. Confirmed that the heater element of the right (or left) upstream O2 sensor is within specification (in this test).

... Your next step is to go to: TEST 4: Checking the Continuity Between the O2 Sensor and PCM.

CASE 2: The upstream O2 sensor heater element’s resistance is NOT within specification and/or there’s continuity between the other terminals. This test result indicates a problem with the heater element of the upstream oxygen sensor you’re testing. Replace the oxygen sensor.

TEST 4: Checking the Continuity Between the O2 Sensor and PCM


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The last battery of tests is to make sure that the wire that connects to terminal number 2 of the right (or left) upstream oxygen sensor isn’t shorted to ground or is ‘open’ somewhere between the sensor’s harness connector and the PCM’s connector.

This can easily be accomplished by doing a continuity test between the right (or left) upstream O2 sensor engine harness connector and the PCM harness connector and a continuity test between terminal number 2 and ground.

NOTE: The left upstream oxygen sensor terminal number 2 wire connects to pin number 51 of the PCM connector. The right upstream oxygen sensor terminal number 2 wire connects to pin number 50 of the PCM connector.

These are the step tests:

1.1Disconnect the battery’s negative terminal and:

Disconnect the upstream oxygen sensor (that you need to test) from its engine harness connector.

Disconnect the PCM from its harness connector.

2.2Testing the right upstream O2 sensor, test continuity between:

Terminal number 2 of the O2’s engine harness connector and terminal 50 of the PCM’s harness connector.

Continuity should exist.

3.3Testing the left upstream O2 sensor, test continuity between:

Terminal number 2 of the O2’s engine harness connector and terminal 51 of the PCM’s harness connector.

Continuity should exist.

4.4Test the continuity between:

Terminal number 2 and engine ground (see illustration 2 of 2).

This test applies to both the right or left upstream oxygen sensor.

Continuity should NOT exist.

CASE 1: All of the continuity tests showed no problems. This test result tells you that that are no ‘opens’ or shorts to ground in the circuit between the PCM’s harness and the O2 sensor’ harness connector.

Since you’ve reached this point because you have:

1. Confirmed that the right (or left) upstream O2 sensor is stuck producing a continuous voltage in TEST 1.

2. Confirmed that the right (or left) upstream O2 sensor does NOT react to a manually induced rich condition TEST 2.

3. Confirmed that the heater element of the right (or left) upstream O2 sensor is within specification in TEST 3.

... You can correctly assume that the upstream O2 sensor you’re testing is fried and needs to be replaced with a new one.

CASE 2: One or several of the continuity tests showed a problem. Check all ofyour connections and repeat a test one more time.

If the continuity tests confirm the problem... then repair the short to ground or the ‘open’ in the circuit. Repairing this issue will solve the right or left upstream O2 sensor diagnostic trouble code (P0130 or P0150) lighting up the check engine light on your Nissan Pathfinder.

Where to Buy your NissanPathfinder’s O2 Sensors and Save

If you walk into your local auto parts store you'll notice that the upstream O2 sensors for Bank 1 (right) and Bank 2 (left) are expensive. If you do need to buy new O2 sensors, check out the links below and save:

Right UpstreamDirect Fit

Right UpstreamDirect Fit

Left UpstreamDirect Fit

Left UpstreamDirect Fit

More Nissan Pathfinder Test Tutorials




How to Test the Idle Switch (Nissan 3.3L Pathfinder, Xterra, Frontier)

August 15, 2013

Updated: March 17, 2014


The idle switch on your 3.3L Nissan Pathfinder (Frontier, Xterra, QX4) is part of the throttle position sensor assembly and can be easily tested with a simple multimeterresistance test.

In this tutorial, I'm gonna' show you how to test it and how to adjust it (if you need to replace it).

Here are the contents of this tutorial at a glance:

Idle Switch Continuity Tests. Adjusting the Throttle Position Sensor Assembly. Where to Buy Your TP Sensor and Save. More Nissan 3.3L Test Tutorials.

If you need to test the throttle position sensor part of the idle switch, this tutorial willhelp:Throttle Position Sensor Test (Nissan 3.3L Pathfinder, Xterra, Frontier).

Idle Switch Continuity Tests


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Testing the idle switch involves measuring continuity between specific pins of the throttle position sensor assembly.

Since the TP sensor assembly is 2 sensors in 1 and has two connectors.... the pinsthat we're going to be testing are the ones that the gray connector connects to and these are labeled with the numbers 4, 5 and 6 in the illustration in the image viewer.

The bottom brown connector connects to the TP sensor part and supplies it with power, ground, and relays the throttle angle voltage signal to the PCM.

Idle Switch Closed Throttle Specifications

Throttle Angle Pins Ohms

Closed Throttle 5 and 6 No Continuity

Open Throttle 5 and 6 No Continuity

Idle Switch Open Throttle Specifications

Throttle Angle Pins Ohms

Closed Throttle 4 and 5 Continuity

Open Throttle 4 and 5 No Continuity

If the throttle switch on your Nissan Pathfinder (Xterra, Frontier, QX4) doesn't pass any of the above pin continuity tests... then, before replacing it, you need to make sure that it's not misadjusted. The next subheading will help you with this procedure.

Adjusting the Throttle Position Sensor Assembly


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If you need to remove and replace the throttle position sensor assembly... you'll need to adjust it to the correct specification before you bolt it down.

This is a pretty easy adjustment and in this section I'll show you how to do it.

NOTE: The TP sensor assembly needs to be connected to its connectors for this adjustment to take place.


1. Turn the ignition switch to its Off position and make sure the TP sensor assembly is connected to its connectors.

2. Turn the ignition switch to its On position but don't start the engine.3. Place your multimeter in Volts DC mode and:

Connect the red multimeter lead to the wire that connects to the pin labeled with the number 2 (see the illustration in theimage viewer above).

Ground the black multimeter lead on the battery negative terminal.

NOTE: Remember the throttle position sensor assembly must remain connected to its connectors through the entire adjustment.

4. Adjust the TPS sensor by rotating it until the output voltage is within specification:

Specification: .3 to .7 volts DC.5. Once the output voltage has reached the above voltage specification,

tighten the TP sensor assembly mounting bolts.6. Once you're done, recheck the output voltage to make sure the TP sensor

didn't move on you when you tightened the two bolts.

Where to Buy Your TP Sensor and Save

Just recently one of my cousins needed to buy a TP sensor for her 1998 Nissan Pathfinder and I was shocked and how much paid for it at our local auto parts store! After all, the TP sensor she bought is a no-name brand Chinese knockoff that she paid over $100 (US) for.

I didn't have the heart to tell her that she could've bought it a whole lot cheaper online, but I will tell you and I'll show you where to buy it. You can buy it here:

Not sure the TP sensor listed fits your particular Nissan? Don't worry, they'll make sure it fits your Nissan, once you get to the TP sensor site, or they'll find the right one for you.

More Nissan 3.3L Test Tutorials

If this tutorial was helpful/informative, you can find a complete list of tutorials here: Nissan 3.0L, 3.3L, 3.5L Index of Articles.

Here's a sample of the tutorials you'll find there:

How to Troubleshoot a No Start (Nissan 3.0L, 3.3L, 3.5L). How to Test Engine Compression (Nissan 3.0L, 3.3L, 3.5L). Mass Air Flow (MAF) Sensor Test 3.3L Frontier, Quest, Pathfinder,

XTerra(at: easyautodiagnostics.com). How to Bench test a Starter Motor (Step by

Step) (at:easyautodiagnostics.com).

Throttle Position Sensor Test (Nissan 3.3L Pathfinder, Xterra, Frontier)

August 14, 2013

Updated: March 17, 2014


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As you're probably already aware, the throttle position sensor on your Nissan is two sensors in 1. One part of the assembly is the actual TP sensor and the other part is the idle switch.




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Testing the throttle position sensor (TPS) to see if it has failed and causing a TPS diagnostic trouble code (DTC) is not hard.

In this tutorial, I'm gonna' show you how to troubleshoot the throttle position sensor(TPS) on your Nissan 3.3L Pathfinder (Frontier, XTerra or QX4), with a multimeter and in a step-by-step way.

I'm also gonna' show you how to adjust it after removing and replacing it (you can find these instructions on the last page of this tutorial).

Here are the contents of this tutorial at a glance:

Symptoms of a Bad Throttle Position Sensor (TPS). How the Throttle Position Sensor (TPS) Works. Circuit (Wire) Descriptions of the TPS. START HERE: Troubleshooting the TP Sensor. TPS TEST 1: Testing the TPS Voltage Signal. TPS TEST 2: Verifying TPS Has Power. TPS TEST 3: Verifying TPS Has Ground. How to Adjust the Throttle Position Sensor Assembly. Where to Buy Your TP Sensor and Save. More Nissan 3.3L Test Tutorials.

If you need to test the idle switch part of the TP sensor assembly, the following tutorial will help: How to Test the Idle Switch (Nissan 3.3L Pathfinder, Xterra, Frontier).

Symptoms of a Bad Throttle Position Sensor (TPS)

Since the throttle position sensor is one of several sensors that your Nissan's fuel injection computer uses to calculate how much much fuel to inject, when it fails you're going to see several symptoms.

1. Check engine light (CEL) shining nice and bright.2. Diagnostic trouble codes (DTC) stored in the PCM's memory:

P0120: TP Sensor A Circuit Malfunction.3. Your Nissan Pathfinder (Xterra, Frontier) fails the state mandated emissions

test.4. Bad gas mileage.5. Hard start and/or extended cranking time (after shut off).6. Black smoke coming out of the tailpipe.7. Hesitation when accelerating your Pathfinder down the road.

How the Throttle Position Sensor Works



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As you're probably already aware, the throttle position sensor (TPS) on your 3.3L equipped Nissan Pathfinder (Frontier, Xterra or QX4) is attached to the throttle body and its job is to measure throttle plate angle.

In layman's terms, this means that the TPS is tasked with the job of measuring howmuch you step on or step off the accelerator pedal as you're driving the down the road.

This throttle plate angle information is then sent to your Nissan's fuel injection computer as a voltage DC signal.

To give you a few more specifics:

1. As you step on the accelerator pedal, The throttle plate opens and the TP sensor measures how

much and relays this to the PCM. The fuel injection computer injects more fuel.

2. As you let your foot off the accelerator pedal, The throttle plate closes and the TP sensor measures how

much and relays this to the PCM. The fuel injection computer injects less fuel.

Circuit (Wire) Descriptions of the TPS


Image 1 of 2

The throttle position sensor (TPS) on your 3.3L equipped Nissan Pathfinder (Frontier, Xterra or QX4) is located on the side of the throttle body.

As you can see in photo 2 of 2 (in the image viewer) the TP sensor has 2 connectors for a total of 6 wires coming out of both. This is due to the fact that the throttle position sensor is two sensors in one. One part of the assembly is the idle switch and the other part is the throttle position sensor itself.

The bottom brown connector connects to the TP sensor part and supplies it with power, ground, and relays the throttle angle voltage signal to the PCM. The gray connector connects to the idle switch part of the assembly.

To better understand how we're gonna' test the throttle position sensor (TPS), in this tutorial, I'm going to briefly describe each wire's job and how the sensor works.

TP sensor brown connector:

1. The TP sensor is a 3 wire sensor. Wire that connects to pin labeled with the number 1.

o Feeds ground to the TP sensor.o Ground is provided by the PCM (internally).

Wire that connects to pin labeled with the number 2.o Feeds the throttle angle voltage signal to the

PCM.o This voltage signal varies depending on the

amount of throttle plate opening. Wire that connects to pin labeled with the number 3.

o Feeds power to the TP sensor.o In the form of 5 Volts DC and is supplied only

with Key On Engine Off (KOEO) or Key On Engine Running (KOER).

o Power comes directly from the PCM.

REMEMBER: The throttle position sensor (TPS), at closed throttle, produces a lowvoltage signal of around .5 Volts DC. As the throttle plate starts to open (as you step on the accelerator pedal and accelerate the engine), this .5 Volt signal starts to increase. At wide open throttle, the TP sensor will output about 4.5 Volts DC.

With this bit of information, let's move on to the next subheading...

START HERE: Troubleshooting the TP Sensor

The key to diagnosing the your 3.3L equipped Nissan Pathfinder (Frontier, Xterra or QX4)'s throttle position sensor (TPS) is to remember that:

1. The TP sensor's voltage signal increases when the throttle plate opens2. The TP sensor's voltage decreases when the throttle plate closes.

So, the absolute best way to find out if the TPS has failed on your Nissan is by manually testing the TP sensor with a multimeter (while it's still on the throttle body and connected to its electrical connector).

Here's a summary of the 3 tests in this tutorial:

1. Check the TP sensor's voltage signal with a multimeter. You'll be connecting your multimeter to the TP sensor

connector's middle wire and then manually opening and closing the throttle to see if the TP sensor produces a varying DC voltage signal.

TEST 1: Testing the TPS Voltage Signal.2. Verify that the TP sensor is getting power (if TEST 1 is failed).

This is a simple multimeter test too. TEST 2: Verifying TPS Has Power.

3. Verify that the TP sensor is getting ground (if TEST 1 is failed). This is a simple multimeter test too. TEST 3: Verifying TPS Has Ground.

TPS TEST 1: Testing the TPS Voltage Signal





Image 1 of 2

The very first thing that we're going to do is connect a multimeter to the wire that connects to the TPS pin labeled with the number 2 (this is the middle wire of the brown connector).

Once the multimeter is connected, we'll manually rotate the throttle plate to see if the throttle position sensor is creating a throttle angle signal.

While we're verifying the throttle angle voltage, we're gonna' gently tap the TP sensor with a screwdriver's handle to see if it affects the voltage output.

I'll explain everything in a step-by-step manner in the following instructions.

NOTE: To ensure the accuracy of your test, it's best to test the throttle position sensor (TPS) with the engine warmed up.

OK, let's start:

Part 1

1.1Place your multimeter in Volts DC mode and with the RED multimeter lead, probe the wire that connects to the TP sensor pin labeled with thenumber 2 in the image (in the image viewerabove). This is the circuit that supplies the TP Signal to the PCM.

If you don't have a multimeter or need to upgrade yours, check

out my recommendation: Abe's Multimeter Recommendation (found at:easyautodiagnostics.com).

NOTE: The throttle position sensor has to remain connected toits connector for this test to work (this is where a wire piercing probe comes in handy to get to the signal inside the wire. To see what one looks like, click here: Wire Piercing Probe Tool.)

2.2Ground the BLACK multimeter test lead on the battery negativeterminal. Have you helper turn the Key On, but don't start the engine (this will power up the TP sensor).

3.3Your multimeter should report .4 to .9 Volts DC. If your multimeter doesn't, don't worry about it just yet, continue with the other steps.

Part 2

1.4Now, slowly open the throttle (by hand and from the engine compartment) while you observe the change in voltage numbers on your multimeter.

For this test result to be accurate, you need to open the throttleby hand and not from inside the vehicle.

2.5As the throttle opens, the voltage numbers will increase. This increase in voltage should be smooth and without any gaps or skips. Once the throttle is wide open, your multimeter should read somewhere between 3.5 to 4.9 Volts DC.

3.6




Now, slowly close the throttle. As the throttle is closing, you should see the voltage decrease smoothly and without any gaps or skips, to the exact same voltage you noticed in step 4.

Part 3

1.7OK, now you'll need someone to help you lightly tap on the throttle position sensor with the handle of a screw-driver (or something similar, and I want to emphasize the words ‘lightly tap') as you slowly open and close the throttle and observe the multimeter.

If the TPS is bad, the tapping will cause the voltage numbers toskip or go blank. If the TPS is OK, the tapping will have no effect on the voltage numbers.

2.8Repeat step 7 several times to make sure of your multimeter test results.


CASE 1: Multimeter registered a smooth increase or decrease in voltage withno gaps. This test result tells you that the TP sensor on your 3.3L Nissan Pathfinder (Xterra, Frontier, QX4) is working correctly and that it's not malfunctioning at this time.

This test result also let's you know that the problem causing the P)120 trouble codeis intermittent and not present at this point in time.

CASE 2: Multimeter DID NOT register a smooth increase or decrease in voltage, and you saw the voltage reading skip or go dead when tapping the TPS... then this means that the throttle position sensor (TPS) is BAD. Replace the throttle position sensor.

Go to Where to Buy Your TP Sensor and Save.


NOTE: After replacing the TPS, you'll need to adjust it. For the TPS adjustment instructions, go to: How to Adjust the Throttle Position Sensor Assembly.

CASE 3: Multimeter DID NOT register any voltage, this test result doesn't condemn the TPS as BAD just yet. Why? Because...

... the TPS may be missing either power or ground. So the next step is to check that the TPS is getting power, go to TPS TEST 2: Verifying TPS Has Power.

TPS TEST 2: Verifying TPS Has Power


Image 1 of 2

If you've reached this point, it's because in TEST 1 your 3.3L Nissan Pathfinder's (Xterra, Frontier, QX4) TP sensor did not produce a throttle angle signal.

There's a good chance that the cause of this test result is that the TP sensor is either missing power or ground.

So in this test we're going to check to see if the TP sensor is being fed with power on the wire that connects to the TP sensor pin labeled with the number 3.



As stated earlier, this power is in the form of 5 Volts DC and is feed to the TP sensor by the PCM.

NOTE: You can test for these 5 Volts DC with the TP sensor connected or disconnected to the TPS. I personally prefer to do this test with the TP sensor's connector unplugged.


1.1Set your trusty multimeter's dial to Volts DC mode.

2.2Probe the wire that connects to your Nissan's TP sensor pin number 3, with the RED multimeter lead and an appropriate tool (like a Wire-Piercing Probe). The throttle position sensor's connector can be connected to the sensor or not when you probe this circuit.

IMPORTANT If you probe the front of the TPS connector, be careful and don't damage the terminal. Damaging the terminal will require that you replace the connector.

3.3Connect the BLACK multimeter lead to a good and clean ground point on the engine or directly on the negative (-) battery terminal.

4.4When you've set up the test, have a helper turn the Key On Engine Off (KOEO).

5.5

Your multimeter should display 4.5 to 5 Volts on its screen. OK,now let's interpret your test results below:

CASE 1: Multimeter registered 4.5 to 5 Volts, this confirms that the TP sensor is being fed with power (4.5 to 5 Volts DC).

The next step is to test the ground circuit of the throttle position sensor, go to TPS TEST 3: Verifying TPS Has Ground.

CASE 2: Multimeter DID NOT register 4.5 to 5 Volts, Recheck your connections and repeat the test. If your multimeter still doesn't register the 4.5 to 5 Volts DC...

... then you've just eliminated the TP sensor itself as bad. The two most likely reasons for this are: 1) an open short in the circuit or 2) the PCM may be fried (although a bad PCM is very rare).

Although it's beyond the scope of this article to test these two conditions, you have now eliminated the throttle position sensor (TPS) on your Honda as being the cause of the problem and/or the TPS diagnostic trouble code (DTC) lighting up the Check Engine Light (CEL).

TPS TEST 3: Verifying TPS Has Ground




Image 1 of 2

So far you've confirmed that the TP sensor:

One: Is not producing a throttle angle voltage signal in TPS TEST 1.

Two: that it's getting power on the wire that connects to the TP sensor pin labeled with thenumber 2 of the brown connector in TPS TEST 2.

... the next step (and the purpose of this last test) is to see if it's being fed with ground by the wire that connects to TP sensor pin labeled with the number 1, in the illustration in the image viewer.

IMPORTANT: Remember, the PCM is the one that provides this ground internally...so be careful and don't accidentally or intentionally apply power (12 Volts) to this circuit or you'll fry the PCM.

OK, here are the test steps:

1.1With your multimeter still in Volts DC mode from TPS TEST 2.

2.2Probe the wire that connects to the TP sensor pin labeled with thenumber 1 in the photos with the BLACK multimeter lead. The TPS connector can be connected or not to the sensor.

It's important that you do not probe the front of the connector oryou run the risk of damaging the terminal.

3.3Now, with the RED multimeter lead, probe the battery positive (+) terminal.



4.4Once again, when everything is ready, have your helper turn the Key to its ON position but don't start the engine.

5.5If this circuit is OK and the PCM is providing a good path to ground, your multimeter will display 11 to 12 Volts.

CASE 1: Multimeter showed 11 to 12 Volts, this confirms that the PCM and the wire/circuit (that supply this ground) are OK.

All three test have confirmed that:

1. Your 3.3L Pathfinder's (Frontier, Xterra, QX4) TPS is not providing a throttleplate angle signal when manually opening the throttle plate (TPS TEST 1).

2. The TPS is being fed 5 Volts DC (TPS TEST 2).3. The TPS is being fed ground.

Therefore, you can conclude that the TP Sensor is BAD and needs to be replaced. The new TPS will need to be adjusted before you take your Nissan on the road andthe following tutorial will show you how: Adjusting the Throttle Position Sensor Assembly.

CASE 2: Multimeter DID NOT show 11 to 12 Volts, Recheck your connections and repeat the test. If your multimeter still doesn't show the indicated voltage...

...then this indicates a problem with either the PCM (internal fault/problem) or an open in the wire between the TPS and the PCM itself.

Although testing these two conditions are beyond the scope of this article, you have now eliminated the throttle position sensor (TPS) on your Honda as being thecause of the problem and/or the TPS Diagnostic Trouble Code (DTC) lighting up the Check Engine Light (CEL).

How to Adjust the Throttle Position Sensor Assembly






Image 1 of 2

If you have removed the throttle position sensor (TPS) and have replaced it, you'll need to adjust it to the correct specification.

Thankfully, adjusting the TPS isn't hard and can be done with the same multimeter you used to test it in the previous pages. In this section I'll show you how.

NOTE: The TP sensor assembly needs to be connected to its connectors for this adjustment to take place.


1. Turn the ignition switch to its Off position and make sure the TP sensor assembly is connected to its connectors.

2. Turn the ignition switch to its On position but don't start the engine.3. Place your multimeter in Volts DC mode and:

Connect the red multimeter lead to the wire that connects to the pin labeled with the number 2 (see the illustration in theimage viewer above).

Ground the black multimeter lead on the battery negative terminal.

NOTE: Remember the throttle position sensor assembly must remain connected to its connectors through the entire adjustment.

4. Adjust the TPS sensor by rotating it until the output voltage is within specification:

Specification: .3 to .7 volts DC.5. Once the output voltage has reached the above voltage specification,

tighten the TP sensor assembly mounting bolts.6. Once you're done, recheck the output voltage to make sure the TP sensor

didn't move on you when you tightened the two bolts.

Where to Buy Your TP Sensor and Save

Just recently one of my cousins needed to buy a TP sensor for her 1998 Nissan Pathfinder and I was shocked and how much paid for it at our local auto parts store! After all, the TP sensor she bought is a no-name brand Chinese knock-off that she paid over $100 (US) for.

I didn't have the heart to tell her that she could've bought it a whole lot cheaper online, but I will tell you and I'll show you where to buy it. You can buy it here:

Not sure the TP sensor listed fits your particular Nissan? Don't worry, they'll make sure it fits your Honda, once you get to the TP sensor site, or they'll find the right one for you.

More Nissan 3.3L Test Tutorials

If this tutorial was helpful/informative, you can find a complete list of tutorials here: Nissan 3.0L, 3.3L, 3.5L Index of Articles.

Here's a sample of the tutorials you'll find there:

How to Troubleshoot a No Start (Nissan 3.0L, 3.3L, 3.5L). How to Test Engine Compression (Nissan 3.0L, 3.3L, 3.5L). Mass Air Flow (MAF) Sensor Test 3.3L Frontier, Quest, Pathfinder,

XTerra(at: easyautodiagnostics.com). How to Bench test a Starter Motor (Step by

Step) (at:easyautodiagnostics.com).








ENCENDIDO ELECTRONICO NISSANSISTEMAS DE ENCENDIDO ELECTRONICO PARA UNIDADES NISSAN

ESTE SISTEMA SE DA A CONOCER EN 1988 EN LAS UNIDADES NINJA TURBO CON MOTOR 1600.MAS TARDE ELSISTEMA ES INCORPORADO A LAS UNIDADES HIKARY Y FINALMENTE EL SISTEMASE INCORPORA EN LA ICHIVAN Y PICK UP HASTA 1993 EN MOTOR DE 2.4 LTS .ESTE SISTEMA LO UTILIZAN EN EL TSURU HASTA 1992 MOTOR E-16 ESTA UNIDAD ES LA ULTIMA QUE SALIO CARBURADA Y TIENEN UN CARBURADOR NIKKI 2 GARGANTAS, LAS ESPREAS DE GASOLINA SON LAS SIGUIENTES: CIRCUITO PRIMARIO 104 Y 107 CABE SEÑALAR QUE EN NISSAN ESTE CIRCUITO SE BASA LA CANTIDAD DE AIRE QUE LE DEBERA LLEGAR AL CARBURADOR, PARA EL SECUNDARIO SERAN LA 130 Y 140 EN ESTE CIRCUITO SE ENCARGA DE LA POTENCIA Y DESEMPEÑO DEL MOTOR, Y LAS ESPREAS DE AIRE EN EL CIRCUITO PRIMARIO ES 70 Y EN EL SECUNDARIO 60 , LA VALVULA DE FUERZA SON LA 40,45 Y EN OCASIONES LA 60. EN CUALQUIER CARBURADOR TRATE PRIMERO DE AJUSTAR LA MEZCLA AIRE/COMBUSTIBLE ABRIENDO O CERRANDO LA ESPREA DEL AIRE SI LOGRA LA MEZCLA IDEAL ,REVISE LA INYECCION DE COMBUSTIBLE DEL CARBURADORY SI DUDA DE SU FUNCIONAMIENTO REEMPLAZE EL INYECTOR DEL CARBURADOR ESTANDO PUESTO EL CARBURADOR DE PREFERENCIA , SI AL TAPAR EL CARBURADOR CON LA MANO SE COMPONE ESE CARBURADOR PROBABLEMENTE SEA NECESARIO REEMPLAZARLO SI ES UN NIKKI O UN HOLLEY DOS GARGANTAS QUE VAN EN LA SERIE K ,LO QUE PUEDE HACER EN UN MOMENTO DADO PARA SOLUCIONAR EL PROBLEMA ES COMPRAR EL REPUESTO ORIGINAL JAPONES PARA EL CARBURADOR NIKKI, HAGA SIEMPRE ESTAS PRUEBAS Y SI NO SE CORRIGIO EL PROBLEMA NO TRATE DE ARREGLARLO SI NO TIENE BASTANTE EXPERIENCIA EN CARBURADORES, MANDE AL CLIENTE A LA AGENCIA O BIEN A UN TALLER QUE SOLO SE ESPECIALIZAN EN REPARACIONES DE CARBURADORES QUE CUENTEN CON TORNO.

EL SISTEMA DE ENCENDIDO ELECTRONICO SE DA A CONOCER EN DOS TIPOS :EL PRIMER SISTEMA SE CARACTERIZA POR UTILIZAR EL MODULO DE ENCENDIDO ELECTRONICOSUJETO EN LA PARTE EXTERIOR DEL DISTRIBUIDOR.EL SEGUNDO SISTEMA EL CUAL FUE EMPLEADO EN EL TSURU EL MODULO DE ENCENDIDO ELECTRONICO SE ENCONTRARA DENTRO DEL DISTRIBUIDOR.

ESPECIFICACIONES TECNICAS DE LOS COMPONENTES DEL SISTEMA.

1.- BOBINA DE ENCENDIDO.- VALORES DE RESISTENCIA.RESISTENCIA DEL DEVARIADO PRIMARIO DE .5 A 1 OHMS.2.- DEVANADO SECUNDARIO DE 10 A 12 KILOHOMS.DEL NEGATIVO DE LA BOBINA A LA TORRETA CENTRAL.NOTA: AL REALIZAR ESTA PRUEBA EL MULTIMETRO DEBERA DE ENCONTRARSE EN

200 OHMS EN EL DEVARIADO PRIMARIO Y PARA EL SECUNDARIO EN 20 OHMS.

EN ESTA MARCA LA BOBINA TIPO BOTELLA DEBE SER ORIGINAL

BOBINA CAPTADORA .- ES UNA GENERADORA DEL VOLTAJE LA CUAL MANEJA UN RANGODE 0 A 5 VOLTS DE CORRIENTE ALTERNA (VCA).LA RESISTENCIA ES DE 350 A 400 OHMS.LA CALIBRACION ES DE .012 A .020 MILESIMAS DE PULGADA.

PRUEBA DEL BANCO DEL MODULO DE ENCENDIDO.PASO 1.- ALIMENTACION DE TIERRA FISICA AL CUERPO.PASO 2 .- ALIMENTACION DE CORRIENTE EN LA TERMINAL B.PASO 3 .- CONECTAR LAMPARA DE PRUEBAS A CORRIENTE A LA LETRA C.NOTA: AL REALIZAR ESTE PROCEDIMIENTO NO DEBERA DE ENCENDER LA LAMPARA DEPRUEBA DE LO CONTRARIO EL MODULO NO SIRVE.PASO 4 .- ATRAVEZ DE UNA LAMPARA DE PRUEBAS A CORRIENTE EXCITE LA LETRAG (GREEN -VERDE).NOTA : AL REALIZAR ESTE PROCEDIMIENTO DEBERA DE ENCENDER LA PRIMER LAMPARADE PRUEBA CONECTADA EN LA LETRA C. DE ENCENDER LA LAMPARA ESO INDICA QUE ELMODULO SI FUNCIONA.PARA DIFERENCIAR LA CORRIENTE DE ACCESORIOS CON LA DE IGNICION ES QUE CUANDOSE GIRE LA LLAVE A LA POSICION START LA CORRIENTE DE ACCESORIOS SE CORTA.

ESTA FALLA ES INTERMITENTE POR LO QUE SE SUGIERE TENER OTRO DISTRIBUIDOR A LA MANO PARA QUITAR Y PONERLO EN EL MOMENTO DE LA FALLA.

HISTORIAL PARA LAS UNIDADES NISSAN

ESTE SISTEMA SE DA A CONOCER POR PRIMERA VEZ EN 1991 EN LAS UNIDADES HIKARI,LAS CUALES UTILIZAN EL MOTOR E16ET (4 cil. 1.6 lts turbo).EN ESTE MISMO AÑO SE DAN A CONOCER DOS UNIDADES NUEVAS DE IMPORTACIONEL MAXIMA MOTOR VG30E Y EL 300ZX AMBAS UNIDADES UTILIZAN UN MOTOR V6 DE 3.0 LTSCON DOBLE ARBOL DE LEVAS EN LA CABEZA , 24 VALVULAS.EN EL 300 ZX CUENTA ADEMAS DE DOBLE TURBO ES DECIR EL MOTOR VG30DETT.1992 EN ESTE AÑO SE DA A CONOCER EL PRIMER SENTRA DE IMPORTACION CON CARROCERIAB13 CUENTA CON UN MOTOR GA16DE O QUE ES DE 4 CIL 1.6 LTS, DOBLE ARBOL DE LEVAS,16VALVULAS.1993 EN ESTE AÑO SE DA A CONOCER EL PRIMER TSURU CON SISTEMA DE INYECCION DECOMBUSTIBLE EL CUAL UTILIZA EL MOTOR E 16 E.AL TSURU TAMBIEN SE LE INCORPORA EL MOTOR SR 200 DE O QUE ES IGUAL UN MOTOR DE 4CILINDROS DE 2

LITROS Y QUE CUENTA CON DOBLE ARBOL DE LEVAS Y 16 VALVULAS.EN ESTE AÑO LA TSUBAME SALE POR PRIMERA VEZ CON UN MOTOR 1.6 LTS, 4 CIL, DOBLE ARBOLDE LEVAS ( GA16DE).EN 1994 EN ESTE AÑO APARECE POR PRIMERA VEZ LA PICK UP CON SISTEMA DE INYECCIONELECTRONICA DE COMBUSTIBLE. CUENTA CON UN MOTOR DE 4 CIL ; 12 VALVULAS Y 2.4 LTS(KA24E).EN ESTE MISMO AÑO APARECE EL TSURU CON UN MOTOR DE 4 CIL,2.4 LTS,12 VALVULAS(KA2AE) Y CON CARROCERIA D21.1995 EN ESTE AÑO APARECEN LAS PRIMERAS UNIDADES INFINITI CON UN MOTOR V8 DE 4.5 LTSDOBLE ARBOL DE LEVAS, 32 VALVULAS (BH45DE).1996 EN ESTE AÑO SE DAN A CONOCER UNA GRAN VARIEDAD DE MOTORES Y UNIDADES: POREJEMPLO SENTRA, LUCINO SERIE B14.SENTRA MOTOR DE 4 CIL 1.6 LTS DOBLE ARBOL DE LEVAS (GA16DNE)LUCINO MOTOR DE 4 CIL 2.0 LTS 16 VALVULAS DOBLE ARBOL DE LEVAS (SR20DE)EN ESTE AÑO APARECE LA PATHFINDER,ALTIMA,MAXIMAPATHTFINDER MOTOR V6 DE 3.3 LTS VG33EALTIMA MOTOR DE 4 CIL 2.4 LTS DOBLE ARBOL DE LEVAS KA24DEMAXIMA MOTOR DE 6 CIL 3.0 LTS DOBLE ARBOL DE LEVAS VG30DE1997 EN ESTE AÑO APARECEN LAS UNIDADES QUEST SALIO CON 2 MOTORES EN EL PRINCIPIOCON MOTOR V6 DE 3.3 LTS VG33E Y EN EL 99 TIENE EL MOTOR V6 DE 3 LTS VG30E, EN ESTE MISMO AÑO APARECE EL INFINITI CON MOTOR V8 DE 4.1 LTS DOBLE ARBOL DE LEVAS 32 VALVULAS BH41DE.1998 EN ESTE AÑO APARECE EL INFINITI CON MOTOR V6 DE 3.0 LTS 24 VALVULAS DOBLE ARBOLDE LEVAS VQ30DE.1999 EN ESTE AÑO APARECE UN CAMBIO EN EL TSUBAME SE LE INCORPORA EL MOTOR DE 4 CIL1.6 LTS, 16 VALVULAS, DOBLE ARBOL DE LEVAS GA16DND.2000 EN ESTE AÑO APARECEN DOS NUEVAS UNIDADES LA XTERRA Y LA URVAN EL XTERRA TRAE UN MOTOR DE 6 CIL 3.3 LTS VG33E Y LA URVAN CUENTA CON UN MOTOR DE 4 CIL, 2.4 LTS DOBLE ARBOL DE LEVAS KA24DE.2001 A LA PATHFINDER SE LE INCORPORA UN MOTOR DE 6 CIL DE 3.5 LTS,DOBLE ARBOL DE LEVAS , 24 VALVULAS, UNA BOBINA POR CILINDRO VQ35DE.EL MAXIMA TRAE EL MOTOR DE 8 CIL 4.5 LTS DOBLE ARBOL DE LEVAS, 32 VALVULAS VH45DE.A PARTIR DE ESTE AÑO LA MAYORIA DE LAS REFACCIONES NISSAN SE FABRICAN EN MÉXICO.EL SENTRA PRESENTA UNA FALLA EN LA CREMALLERA AL MANEJAR LA UNIDAD A 160 KM PUDIENDO DESTRUIRSE Y CAUSAR LESIONES GRAVES A LOS OCUPANTES DE LA UNIDAD, EN LA PICK UP PRESENTO UNA FALLA EN LAS ECM POR LA LOCALIZACION DE

ESTA QUEMANDOSE ALGUNAS POR LLEGARLE AGUA AL ECM, ASI COMO UN CORTO PRESENTA ESTA UNIDAD EN EL POSITIVO DE BATERIA CON EL COFRE Y UN INCENDIO DE TODA LA INSTALACION ELECTRICA AL NO TENER EL CABLE FUSIBLE EN EL POSITIVO DE LA BATERIA Y PRESENTA UN CORTO EN LA BOMBA DE COMBUSTIBLE CON LAS REDILAS ( ESTAQUITAS ) YA QUE PUEDE TROZAR EL CABLE DEL POSITIVO DE LA BOMBA Y ATERRIZARLA EN UN MOMENTO DADO Y TENER UNA FALLA INTERMITENTE EN LA BOMBA.SISTEMA DE INYECCION ELECTRONICA DE COMBUSTIBLE

ESTE SISTEMA SE DA A CONOCER EN 1991 EN LAS UNIDADES HIKARI Y SE LE DA EL NOMBRE DESISTEMA ELECTRONICO CONCENTRADO DEL CONTROL DEL MOTOR (E.C.C.S).

LA COMPUTADORA RECIBE DOS NOMBRES EN NISSAN :1.- UNIDAD DE CONTROL ELECTRICO (ECU).2 .- MODULO DE CONTROL ELECTRICO (ECM).

ESTAS COMPUTADORAS LAS PODREMOS ENCONTRAR CON LOS SIGUIENTES CONECTORES :CONECTOR 1 .- CON 51 CAVIDADES EN TOTAL Y SE DIVIDEN EN 3 CONECTORES :1.- CON 20 CAVIDADES2.- CON 16 CAVIDADES.3.- CON 15 CAVIDADES.ESTO ES EN LAS UNIDADES HIKARI.

SISTEMA ELECTRONICO CONCENTRADO DE CONTROL DEL MOTOR (E.C.C.S).

ESTE SISTEMA UTILIZA UNA COMPUTADORA QUE SE ENCARGA DE CONTROLAR A LOS PRINCIPALES SISTEMAS DEL MOTOR.EL NOMBRE QUE RECIBE ECU ES EL DE UNIDAD DE CONTROL ELECTRONICO, EL DE ECM ES ELMODULO DE CONTROL ELECTRONICO .LOS SISTEMAS QUE TIENE LAS UNIDADES NISSAN SON LAS SIGUIENTES :SISTEMA DE INYECCIONSISTEMA DE PRESION DE COMBUSTIBLESISTEMA DE CONTROL DE TEMPERATURA DEL MOTORSISTEMA DE AIRE ACONDICIONADOSISTEMA DE DIAGNOSTICOSISTEMA DE CONTROL DE EMISIONES CONTAMINANTES.

PARA QUE LA COMPUTADORA CONTROLE CADA UNO DE ESTOS SISTEMAS REQUIERE DE LAINFORMACION DE LOS SIGUIENTES SENSORES.

1.- SENSOR DE ANGULO DE GIRO DE CIGÜEÑAL SE ENCUENTRA DENTRO DEL DISTRIBUIDOR.Nota : ESTE SENSOR CAMBIA DE NOMBRE CUANDO SE LE INTEGRA LA BOBINA DE ENCENDIDO

RECIBE EL NOMBRE DE SENSOR DE POSICION DEL ARBOL DE LEVAS.2.- SENSOR DE FLUJO DE MASA DE AIRE (MAF).3.- SENSOR DE CONTROL DE TEMPERATURA DEL REFRIGERANTE DE MOTOR (ELT).4.- SENSOR DE TEMPERATURA DE ENTRADA DE AIRE (IAT).5.- SENSOR DE GAS DE ESCAPE (SENSOR DE OXIGENO)6.- SENSOR DE POSICION DE LA MARIPOSA DE ACELERACION (TPS)7.- INTERRUPTOR DE PRESION DE ACEITE DE LA DIRECCION HIDRAULICA (PSPS).8.- SENSOR DE VELOCIDAD DEL VEHICULO (VSS)9.- INTERRUPTOR DE PARKING Y NEUTRALLAS COMPUTADORAS DE NISSAN LAS PODEMOS ENCONTRAR CON LOS SIGUIENTES CONECTORESPARA UNIDADES HIKARY E16ET, UTILIZA 3 CONECTORES 1 DE 20 CAVIDADES 1 DE 16 Y EL OTRO DE 15.2.- CONECTOR DE 64 TERMINALES PARA UNIDADES DE MOTOR E16E,GA16DE,GA16DNE,K24E YSR20DENOTA : CONECTOR DE COLOR AZUL .3.- CONECTOR DE 76 TERMINALES PARA UNIDADES CON MOTOR V630E,V630DE.4.- CONECTOR DE 88 CAVIDADES PARA UNIDADES CON MOTOR SR20DE (B14),KA24DE ; SR20DESENTRA, LUCINO ; KA24DE URVAN ; MOTOR VG33E PATHFINDER QUEST, XTERRA YVG30E PARAQUEST.Nota : CONECTOR DE COLOR BLANCO5.- CONECTOR DE 104 CAVIDADES PARA UNIDADES INFINITY, MAXIMA NUEVO, 300ZX NUEVO YLA PATHFINDER 3.ONota: CONECTOR DE COLOR GRIS

PRINCIPALES ALIMENTACIONES PARA LA COMPUTADORA DE LOS MOTORESE16E,GA16DE,GA16DNE,KA24E Y SR20DE SERIE B13.

LOCALIZACION DE LA COMPUTADORA.PARA UNIDADES PICK UP SE ENCONTRARA SUJETA AL PISO DEBAJO DEL ASIENTO DEL COPILOTO .EN AUTOMOVILES SE ENCUENTRA SUJETA AL PISO DETRÁS DE LA CONSOLA CENTRAL.EN LAS UNIDADES HIKARI LA COMPUTADORA SE ENCONTRARA DEBAJO DEL ASIENTO DELCOPILOTO.ALIMENTACIONES PRINCIPALESTIERRAS FISICASCAVIDADES 6,13,39,48,107,108,116 ,42 ADICIONAL PARA UNIDADES PICK UP (D21)Nota : ESTAS ALIMENTACIONES SE TOMAN DEL MULTIPLE DE ADMISION EN TODAS LAS UNIDADES NISSAN.CORRIENTE CONSTANTE DE BATERIA CAVIDADES 46 Y 109 ESTA ULTIMA ES ADICIONAL PARAUNIDADES CON MOTOR SR20DE.Nota : EN AUTOMOVILES ESTA CORRIENTE SE ENCUENTRA PROTEGIDA POR UN FUSIBLE ESLAVON DE 20 AMPERS COLOR CAFÉ SE LOCALIZA JUNTO A LA BATERIA.

EN LAS UNIDADES PICK UP ESTA CORRIENTE UTILIZA CABLE FUSIBLE DE PROTECCION Y SE VA ALOCALIZAR JUNTO AL BORNE POSITIVO DE LA BATERIA.SON 4 CABLES FUSIBLES COLOR NEGRO PROTEGE AL ALTERNADOR, VERDE INTERRUPTOR DEENCENDIDO CAFÉ (CAVIDAD 46 ), CAFÉ CORRIENTE DE ACCESORIOS.CORRIENTE DE IGNICION .- CAVIDAD 36NOTA : ESTA ALIMENTACION NO UTILIZA FUSIBLE DE PROTECCION.NOTA 2 .- EL INTERRUPTOR DE ENCENDIDO SE ENCUENTRA PROTEGIDO POR UN FUSIBLETIPOESLAVON EL CUAL SE LOCALIZA EN LA CAJA DE FUSIBLES JUNTO A LA BATERIA EN AUTOMOVILESEN LAS PICK UP EL INTERRUPTOR SE ENCUENTRA PROTEGIDO POR UN CABLE FUSIBLE (VERDE).12 VOLTIOS ATRAVEZ DEL RELEVADOR DE LA COMPUTADORA (CAVIDADES 38,47,109)NOTA: LA CAVIDAD 109 NO ES ALIMENTACION ATRAVEZ DEL RELEVADOR EN UN MOTOR DE 2LTS (ES CORRIENTE CONSTANTE ).NOTA: ESTE RELEVADOR ES CONTROLADO POR LA COMPUTADORA ATRAVEZ DE UNAALIMENTACION DE TIERRA PROVENIENTE DE LA CAVIDAD 4.ESTA ALIMENTACION LA ENVIALACOMPUTADORA CUANDO RECIBE CORRIENTE DE IGNICION.CORRIENTE DE START CAVIDAD 34NOTA : ESTA ALIMENTACION EN LOS AUTOMOVILES SE ENCUENTRA PROTEGIDA POR UN FUSIBLE DE ENCHUFE DE 10 AMPERS EL CUAL SE LOCALIZA EN LA POSICION 14 EN LA CAJA DE FUSIBLES QUE SE ENCUENTRA DENTRO DE LA UNIDAD. EN LAS PICK UP NO UTILIZA FUSIBLE DE PROTECCION.NOTA 2.- LA COMPUTADORA ATRAVEZ DE ESTA ALIMENTACION ACTIVARA LA INYECCIONSIMULTANEA.CONECTOR DE LA COMPUTADORA DE 64 CAVIDADES

LOCALIZACION DEL RELEVADOR DE LA COMPUTADORA ( E.C.C.S)

EN LAS UNIDADES HIKARY SE ENCUENTRA EN LA CAJA DE RELEVADORES JUNTO A LA BATERIA.SE IDENTIFICARA COMO MAIN RELAY (RELEVADOR PRINCIPAL) COLOR VERDE.EN LAS UNIDADES HIKARI SE ENCUENTRA EN LA CAJA DE RELEVADORES DENTRO DE LA UNIDAD COLOR VERDE.

EN LAS UNIDADES MAXIMA Y 300 ZX SE ENCUENTRA EN LA CAJA DE RELEVADORES JUNTO A LABATERIA SE IDENTIFICARA CON LAS LETRAS EGI.EN EL RESTO DE LOS AUTOMOVILES SE ENCUENTRA JUNTO A LA COMPUTADORA.EN LAS PRIMERAS UNIDADES FUEL INYECTION ERAN VERDES ; LAS MAS RECIENTES SONAZULES.

ANGULO DE GIRO DE CIGÜEÑALFUNCION

ES UN COMPONENTE BASICO DEL SISTEMA ECCS, ESTE ULTIMO DETECTA LA VELOCIDAD DELMOTOR RPM, LA POSICION DE LOS PISTONES Y LA INFORMACION LA ENVIA A LA COMPUTADORAPARA CONTROLAR LOS PRINCIPALES SISTEMAS DEL MOTOR POR EJEMPLO: SISTEMA DE PRESIONDE COMBUSTIBLE ,SISTEMA DE ENCENDIDO, SISTEMA DE INYECCION ETC.EL SENSOR DE ANGULO DE GIRO DEL CIGÜEÑAL TIENE UNA PLACA ROTOR , UN CIRCUITOGENERADOR DE ONDA CUADRADA (SENSOR OPTICO). LA PLACA ROTOR TIENE 360 RANURAS A LA PERIFERIA PARA SEÑALES DE 180 GRADOS Y LOS DIODOS EMISORES DE LUZ Y LOS FOTODIODOS (CAPTADORES DE LUZ) ESTAN ALOJADOS EN EL CIRCUITO GENERADOR DE ONDAS CUADRADAS.

NOTA : CUANDO EL VEHÍCULO DA MARCHA Y NO ENCIENDE PUEDE SER QUE LA BOMBA ELECTRICA NO HAYA PRESION, NO HAY INYECCIÓN Y NO HAY CHISPA LO QUE SE TIENE QUE HACER ES UN PUENTE EN EL ARNES DEL DISTRIBUIDOR EN LOS 2 CONECTORES DE 5 VOLTS CON UN CLIP EN LAS TERMINALES DE SEÑAL DE SINCRONIA Y SEÑAL DE REFERENCIA Y EXCITAR CON TIERRA SI ESTANDO ASI SI FUNCIONAN ESTO QUIERE DECIR QUE EL SENSOR OPTICO ES EL QUE ESTA FALLANDO.

SISTEMA DE ENCENDIDO ELECTRONICO DEL E.C.C.S

ESTE SISTEMA ES CONTROLADO POR LA COMPUTADORA ATRAVEZ DE UN TRANSISTOR DEPOTENCIA EL CUAL SERA CONTROLADO POR MEDIO DE UNA SEÑAL DE MILIVOLTAJE PORLACAVIDAD NUMERO 1 Y SERA ENVIADO SIEMPRE Y CUANDO RECIBA INFORMACION DEL SENSORDE ANGULO DE GIRO DEL CIGÜEÑAL.COMPONENTES QUE INTEGRAN EL SISTEMA DE ENCENDIDO.1.- COMPUTADORA2.- SENSOR DE ANGULO DE GIRO DEL CIGÜEÑAL.3.- TRANSISTOR DE POTENCIA.4.- BOBINA DE ENCENDIDO.5.- RESISTENCIA SENSORA Y CAPACITADORA.

LOCALIZACION DE LAS PARTES DEL SISTEMA

1.- COMPUTADORA EN AUTOMOVILES SE UBICA DETRÁS DE LA CONSOLA CENTRAL SUJETA ALPISO EN LAS UNIDADES PICK UP DEBAJO DEL ASIENTO DEL COPILOTO.

2.- SENSOR DE ANGULO DE GIRO DEL CIGÜEÑAL EN TODAS LAS UNIDADES NISSAN DENTRO DELDISTRIBUIDOR.NOTA: ESTE COMPONENTE EN UNIDADES RECIENTES CAMBIA DE NOMBRE A SENSOR DE POSICION DEL ARBOL DE LEVAS AMBOS REALIZAN LA MISMA FUNCION.

3.-TRANSISTOR DE POTENCIA .-PARA MOTOR E16E Y GA16DE SE UBICA SUJETO EN LA TORRETA DEL AMORTIGUADOR DEL LADOIZQUIERDO (GRIS)UNIDADES CON MOTOR SR20DE .- SUJETO A LA CABEZA DEL MOTOR JUNTO A LA BOBINA DELDISTRIBUIDOR (NEGRO)UNIDADES CON MOTOR KA24E .- SE ENCUENTRA JUNTO A LA BOBINA DE ENCENDIDO EN LASALPICADERA IZQUIERDA DE LA UNIDAD (NEGRO).NOTA.- EN LAS UNIDADES MAS RECIENTES SE ENCUENTRAN INTEGRADO AL SENSOR OPTICO( GENERADOR DE ONDAS CUADRADAS).

4.- BOBINA DE ENCENDIDO .-CON MOTOR E16E LOCALIZADO EN LA PARED DE FUEGO AL LADO IZQUIERDO.5.- RESISTENCIA SENSORA Y CAPACITADORAESTOS 2 COMPONENTES FORMAN UNA SOLA PIEZA Y SE ENCUENTRA SOBRE EL ARNES ENTRE LA6.- BOBINA DE ENCENDIDO Y TRANSISTOR DE POTENCIA.EN LAS UNIDADES RECIENTES SE ENCUENTRAN POR SEPARADO Y SE UBICAN CERCA DELDISTRIBUIDOR.

FUNCION DE LOS COMPONENTES DEL SISTEMA

1.- COMPUTADORA ES LA ENCARGADA DE RECIBIR Y AMPLIFICAR LA SEÑAL DE REFERENCIA Y DE SINCRONIA PARA EL CONTROL DEL TRANSISTOR DE POTENCIA.2.- SENSOR DE ANGULO DE GIRO DEL CIGÜEÑAL LO CONFORMA LA COMPUTADORA DA POSICIONDE LOS PISTONES Y LAS REVOLUCIONES DEL MOTOR PARA QUE ESTAMEMPIEZE A ACTIVAR LOSPRINCIPALES SISTEMAS DEL MOTOR.3.- TRANSISTOR DE POTENCIAESTE COMPONENTE SE ENCARGA DE SATURAR A LA BOBINA DE ENCENDIDO ATRAVEZ DE LOSPULSOS DE TIERRA, UNA VEZ QUE RECIBA LA SEÑAL DE MINIVOLTAJE DE LA CAVIDAD NUMERO 1 DE LA COMPUTADORA.4.- BOBINA DE ENCENDIDOSU FUNCION ES ELEVAR EL VOLTAJE QUE RECIBE POR EL DEVARIADO PRIMARIO ARRIBA DE LOS35000 VOLTS.5.- RESISTENCIA SENSORA Y CAPACITADORA

RESISTENCIA SENSORA TIENE LA FUNCION DE DISMINUIR EL AMPERAJE QUE PROVIENE DELNEGATIVO DE LA BOBINA A LA COMPUTADORA CON ESTA INFORMACION SE MONITOREA ELSISTEMA DE ENCENDIDO.CAPACITOR O CONDENSADOR .- SOLO SE UTILIZA PARA EVITAR QUE LOS ARCOS VOLTAICOS QUE SE GENEREN EN EL SISTEMA DE ENCENDIDO PRODUZCAN INTERFERENCIA EN EL RADIO.

TRANSISTOR DE POTENCIA

TIPO Negativo Positivo Negativo Y TIENE LA FUNCION DE INTERRUPTOREL EMISOR QUE ES LA PARTE CENTRAL DEL COMPONENTE EMITE PULSOS DE TIERRA (LETRA W EN ESTE COMPONENTE) E.BASE EMITE SEÑAL DE MILIVOLTAJE (LETRA P DEL COMPONENTE) (CAVIDAD 1) BCOLECTOR ES LA SALIDA DE PULSOS DE TIERRA Y VA AL NEGATIVO DE LA BOBINA NUMERO DEL COMPONENTE) C

PRUEBA DEL BANCO DEL TRANSISTOR

PROCEDIMIENTOPASO NUMERO 1 ALIMENTACION DE TIERRA EN LA TERMINAL 2 (EMISOR)PASO NUMERO 2 CON LAMPARAS DE PRUEBA CONECTADA A CORRIENTE VERIFICAR QUEENCIENDA LA TERMINAL BPASO NUMERO 3 EXCITAR CON LAMPARA DE PRUEBA A CORRIENTE EN LA TERMINAL BNOTA .- AL REALIZAR ESTE PROCEDIMIENTO EL TRANSISTOR DEBERA MANDAR PULSOS DETIERRA POR COLECTOR.

SENSOR DE POSICION DEL ARBOL DE LEVAS MOTOR EGA16DE,KA24E,GA16DNDE,SR20DE.

ESTE SENSOR ES EL ENCARGADO DE INDICAR A LA COMPUTADORA LA POSICION DE LOSPISTONES ATRAVEZ DE LA SEÑAL DE REFERENCIA Y SINCRONIA LA COMPUTADORA ACTIVARA A LOS PRINCIPALES SISTEMAS DEL MOTOR POR EJEMPLO : INYECCION DE COMBUSTIBLE, SISTEMA DE INYECCION DE COMBUSTIBLE, SISTEMA DE PRESION DE COMBUSTIBLE ETC.NOTA : EN LAS UNIDADES CON MOTOR GA16DNE EL SENSOR DE POSICION DEL ARBOL DELEVAS NO UTILIZA LA PLACA ROTOR CON 364 RANURAS ES DECIR, QUE DESAPARECE LA SEÑAL DE SINCRONIA.

SISTEMA DE PRESION DE COMBUSTIBLE .

ESTE SISTEMA ES CONTROLADO POR LA UNIDAD DE CONTROL ELECTRÓNICA QUIEN SEENCARGARA DE ACTIVAR A LA BOMBA DE COMBUSTIBLE POR MEDIO DE UN RELEVADOR EL CUAL RECIBIRA EN BOBINA TIERRA CONTROLADA DE LA CAVIDAD 104.

AL ACTIVAR EL INTERRUPTOR DE ENCENDIDO SERA POR 5 SEGUNDOS Y UNA VEZ QUE EL MOTOR EMPIEZE A TENER MOVIMIENTO CON LA SEÑAL DE REFERENCIA SERA CONSTANTE .

COMPONENTES QUE INTEGRAN EL SISTEMA

1 .- COMPUTADORA2 .- RELEVADOR DE LA BOMBA DE COMBUSTIBLE.3 .- BOMBA DE COMBUSTIBLE .

LOCALIZACION DE LOS COMPONENTES QUE FORMAN EL SISTEMA DE COMBUSTIBLE.

1 .- COMPUTADORA EN LOS AUTOMOVILES SE ENCUENTRAN DETRAS DE LA CONSOLA CENTRALSUJETA AL PISO Y EN LAS PICK UP Y HIKARI DEBAJO DEL ASIENTO DEL COPILOTO.2.- RELEVADOR DE LA BOMBA DE COMBUSTIBLE.EN LAS UNIDADES PICK UP SE ENCUENTRA EN LA CAJA DE RELEVADORES QUE SE UBICAJUNTO A LA BATERIA.EN LOS AUTOMOVILES SU UBICACION VARIA DE ACUERDO AL MODELO Y LO EQUIPADO QUE SEENCUENTRE LA UNIDAD; AL RELEVADOR LO PODEMOS UBICAR EN 3 PARTES DIFERENTES POREJEMPLO :1.- EN LA CAJA DE RELEVADORES QUE SE ENCUENTRA JUNTO A LA BATERIA.2.- EN LA CAJA DE FUSIBLES QUE SE UBICA EN LA PARTE INFERIOR DEL TABLERO DEL LADOIZQUIERDO.3.- EN LA PARTE INFERIOR DEL LADO IZQUIERDO CERCA DE LA CAJA DE FUSIBLE.

BOMBA DE COMBUSTIBLE

SE ENCUENTRA DENTRO DEL TANQUE DE COMBUSTIBLE Y SE UTILIZA UNA BOMBA DE ALTAPRESION 70 PSI (LIBRAS POR PULGADA CUADRADAS).

NOTA : EN LAS PRIMERAS UNIDADES LA CORRIENTE DE IGNICION QUE LLEGA A LA BOBINA NOUTILIZA FUSIBLE DE PROTECCION.LA PRUEBA DEL RELEVADOR SE HARA ENTRE LAS TERMINALES MAS JUNTAS, POR LO QUE LASTERMINALES MAS SEPARADAS SE CHECAN QUE RECIBAN CORRIENTE Y TIERRA.

REGULADOR DE PRESION DE COMBUSTIBLE.

FUNCION.- ES EL ENCARGADO DE MANTENER LA PRESION ADECUADA EN EL RIEL DE INYECTORES Y LO HACE OBSTRUYENDO EL CAUDAL DE COMBUSTIBLE QUE ENVIA LA BOMBA ELECTRICA DE COMBUSTIBLE. ESTE REGULADOR TRABAJA POR MEDIO DEL VACIO Y NO ES CONTROLADO POR LA COMPUTADORA.

LOCALIZACION .- EN LA GRAN MAYORIA DE LAS UNIDADES NISSAN SE ENCONTRARA SUJETO EN EL RIEL DE INYECTORES ; CON EXCEPCION DEL MOTOR E16E QUE SE ENCUENTRA SUJETO A LA CABEZA DEL MOTOR.

CAUSAS QUE PROVOCA UNA BAJA PRESION EN EL RIEL DE INYECTOPRES.

1.- CEDASO TAPADO2.- BOMBA DE COMBUSTIBLE DAÑADA3.- MANGUERA DE UNION4.- LINEA DE ALIMENTACION PRINCIPAL TAPADA5.- FILTRO DE COMBUSTIBLE TAPADO6 .- REGULADOR DAÑADO

EL DIAFRAGMA PUEDE SER DAÑADO POR EL AGUA QUE HAY EN EL COMBUSTIBLE Y SE CHECA QUE LA LINEA DE VACIO AL MULTIPLE DE ADMISION SI SALE COMBUSTIBLE ESTE COMPONENTE ESTA DAÑADO.

FALLAS QUE PROVOCAN LA BAJA PRESION.

1.- EL MOTOR NO ENCIENDE.2 .- EL MOTOR TARDA EN ENCENDER.3.- MOTOR INESTABLE.4.- PERDIDA DE POTENCIA.5.- TIRONEOS Y JALONEOS.6.- EXPLOSIONES POR EL MULTIPLE DE ADMISION.7.- DESPLAZAMIENTO LENTO DE LA UNIDAD.

CAUSAS QUE PROVOCAN UNA ALTA PRESION EN LOS RIELES DE INYECTORES.

1.- REGULADOR DAÑADO (EL DIAFRAGMA QUEDA EN POSICION CERRADA TODO EL TIEMPO) .2.- FALTA DE VACIO.3.- LINEA DE RETORNO TAPADA.

FALLAS QUE OCASIONAN UNA ALTA PRESION EN EL RIEL DE INYECTORES.

1.- CONSUMO EXCESIVO DE COMBUSTIBLE.2.- HUMO NEGRO.3.- MOTOR ACELERADO.

4.- BAJO RENDIMIENTO DE COMBUSTIBLE.5.- INESTABILIDAD DEL MOTOR.

SISTEMA DE INYECCION DE COMBUSTIBLE.EN LAS UNIDADES NISSAN MEXICANAS SOLO SE UTILIZAN MOTORES CON SISTEMA DE INYECCION ELECTRONICA DE COMBUSTIBLE MULTIPORT, ES DECIR UN INYECTOR POR CILINDRO.DENTRO DE LOS MOTORES NISSAN SE UTILIZAN TRES TIPOS DE INYECCION ELECTRONICA :SIMULTANEA Y SECUENCIAL AMBAS EN UN MISMO MOTOR,INYECCION SIMULTANEA .- ES LA PRIMERA QUE SE PRESENTA AL MOMENTO DE DAR MARCHA AL MOTOR AL RECIBIR ALIMENTACION DE 12 VOLTS EN LA CAVIDAD 34 O 20 LA COMPUTADORAACTIVARA TODOS LOS INYECTORES AL MISMO TIEMPO.INYECCION SECUENCIAL .- UNA VEZ ENCENDIDO EL MOTOR LA COMPUTADORA ATRAVEZ DE LASEÑAL DE REFERENCIA Y SINCRONIA ACTIVARA A LOS INYECTORES EN UN ORDEN ESPECIFICO.POR EJEMPLO SI HABLAMOS DE UN MOTOR E16E SERIA 1342 Y ASI SUCESIVAMENTE DEPENDIENDO DE LOS CILINDROS DEL MOTOR.

CODIGOS DE FALLA DE LAS UNIDADES NISSAN

CODIGO DESCRIPCION11 SENSOR DE ANGULO DE GIRO DEL CIGÜEÑAL 11 SENSOR DE POSICION DEL ARBOL DELEVAS ( UNIDADES NUEVAS ) 12 SENSOR DE FLUJO DE MASA DE AIRE ( MAF) 13 SENSOR DE TEMPERATURA DEL REFRIGERANTE DEL MOTOR ( E.C.T .) 14 SENSOR DE VELOCIDAD DEL VEHICULO ( V.S.S ) 21 SISTEMA DE ENCENDIDO 22 CIRCUITO DE LA BOMBA DE COMBUSTIBLE 25 VALVULA AUXILIAR DE CONTROL DE AIRE ( A.A.C ) 28 SOBRECALENTAMIENTO DEL MOTOR 31 COMPUTADORA EN MAL ESTADO 32 SISTEMA DE RECIRCULACION DE GAS DE ESCAPE ( E.G.R ) 33 SENSOR DE GAS DE ESCAPE (SENSOR DE OXIGENO ) 34 SENSOR DE CASCABELEO ( K.S. ) 35 SENSOR DE TEMPERATURA DE ENTRADA DE AIRE ( IAT ) 43 SENSOR DE POSICION DE LA MARIPOSA DE ACELERACION ( TPS ) 44 TODO EL SISTEMA FUNCIONA CORRECTAMENTE 45 FUGA EN INYECTORES 51 CIRCUITO ABIERTO EN INYECTOR 55 TODO EL SISTEMA FUNCIONA CORRECTAMENTE

NOTA : CADA DESTELLO DEL LED ROJO ES UNA DECENA O CENTENA Y CADA DESTELLO VERDEES UNA UNIDAD.

PROCEDIMIENTO PARA OBTENER CODIGOS DE FALLA EN LAS UNIDADES CON MOTOR

SR20DE, B13,B14 .

EN ESTAS UNIDADES PARA ENTRAR AL SISTEMA DE DIAGNOSTICO NO SE UTILIZA EL CONECTORGRIS DE 14 TERMINALES. LA COMPUTADORA UTILIZA UN SELECTOR DE DIAGNOSTICO EL CUAL NOS AYUDA PARA OBTENER CODIGOS DE FALLA.PASO 1.- ACTIVAR EL INTERRUPTOR DE ENCENDIDO A LA POSICION DE ON .NOTA: VERIFICAR QUE EL FOCO DE AVISO CHECK ENCIENDA.PASO 2 .- GIRE EL SELECTOR DE DIAGNOSTICO COMPLETAMENTE A LA DERECHA EN SENTIDO A LAS MANECILLAS DEL RELOJ ( HIGH ).NOTA : AL REALIZAR ESTE PROCEDIMIENTO EL FOCO DE AVISO DE CHECK DEBE APAGARSE.PASO 3.- ESPERE POR LO MENOS CINCO SEGUNDOS Y REGRESE EL SELECTOR A SU POSICIONNORMAL ( LOW ) ES DECIR EN SENTIDO CONTRARIO A LAS MANECILLAS DEL RELOJ.NOTA: AL REALIZAR ESTE PROCEDIMIENTO EL FOCO DE AVISO CHECK COMENZARA A DESTELLAR MOSTRANDO LOS CODIGOS EN MEMORIA.

PROCEDIMIENTO PARA BORRAR CODIGOS DE FALLA EN UN MOTOR 2 LITROS.PASO 1.- UNA VEZ INTERPRETADO LOS CODIGOS DE FALLA EN EL MOMENTO QUE SE ESTENMOSTRANDO GIRE EL SELECTOR DE DIAGNOSTICO COMPLETAMENTE A LA DERECHA.NOTA : EL FOCO DE AVISO CHECK DEBERA DE APAGARSE.PASO 2.- ESPERE POR LO MENOS 5 SEGUNDOS Y REGRESE EL SELECTOR A SU POSICION NORMAL( LOW ).

NOTA : AL REALIZAR ESTE PROCEDIMIENTO EL FOCO DE AVISO CHECK DEBERA QUEDARENCENDIDO.PASO 3 .- DESACTIVAR EL INTERRUPTOR DE ENCENDIDO A OFF .

SISTEMA DE AUTODIAGNOSTICOEN ESTE SISTEMA PODEMOS DIAGNOSTICAR O DETECTAR LAS FALLAS EN MENOR TIEMPO YAQUE EL SISTEMA ES CONSIDERADO COMO DE AYUDA PARA EL MECANICO EN LAS UNIDADESNISSAN NO ES NECESARIO UN APARATO DE DIAGNOSTICO LO PODEMOS REALIZAR ATRAVEZ DE LA MISMA COMPUTADORA CON LA AYUDA DEL FOCO DE AVISO.NOTA : EN ALGUNAS MARCAS DE SCANNER COMO OTC O SNAP ON AÑADEN UN ACCESORIO QUE HACE UN PUENTE EN LAS CAVIDADES 6 Y 7.

SISTEMA DE AUTODIAGNOSTICO PARA UNIDADES CON MOTOR E16E,GA16DE,GA16DNE.(HACER PUENTE CONECTOR 6 Y 7 )

EN ESTAS UNIDADES PARA PODER ENTRAR AL SISTEMA DE DIAGNOSTICO ES NECESARIOREALIZAR UN PUENTE EN EL CONECTOR DE AUTODIAGNOSTICO EL CUAL SE LOCALIZA JUNTO A LA CAJA DE FUSIBLES QUE SE UBICA DENTRO DE LA UNIDAD DEL LADO IZQUIERDO DEBAJO DEL TABLERO

PROCEDIMIENTO

1.- ACTIVAR EL INTERRUPTOR DE ENCENDIDO A LA POSICION ON.NOTA : EL FOCO DE AVISO CHECK DEBERA DE ENCENDER.2.- REALIZAR UN PUENTE EN EL CONECTOR DE DIAGNOSTICO ENTRE LAS TERMINALES 6 Y 7.NOTA : AL REALIZAR ESTE PUENTE EL FOCO DE AVISO CHECK DEBERA DE APAGARSE.3.- ESPERAR POR LO MENOS 5 SEGUNDOS Y REMOVER EL PUENTE EL FOCO DE AVISO CHECKCOMENZARA A DESTELLAR Y LO HARA DE DOS MANERAS COMENZANDO CON DESTELLOS LENTOS QUE EQUIVALEN A DECENAS Y POISTERIORMENTE DESTELLOS RAPIDOS QUE SERAN UNIDADES.

LISTA DE CODIGOS DE FALLA

CODIGO DESCRIPCION

11 SENSOR DE ANGULO DE GIRO DEL CIGÜEÑAL 11 SENSOR DE POSICON DEL ARBOL DE LEVAS( UNIDADES NUEVAS )12 SENSOR DE FLUJO DE MASA DE AIRE ( MAF) 13 SENSOR DE TEMPERATURA DEL REFRIGERANTE DEL MOTOR ( E.C.T .) 14 SENSOR DE VELOCIDAD DEL VEHICULO ( V.S.S ) 21 SISTEMA DE ENCENDIDO 22 CIRCUITO DE LA BOMBA DE COMBUSTIBLE 25 VALVULA AUXILIAR DE CONTROL DE AIRE( A.A.C)28 SOBRECALENTAMIENTO DEL MOTOR 31 COMPUTADORA EN MAL ESTADO 32 SISTEMA DE RECIRCULACION DE GAS DE ESCAPE ( E.G.R ) 33 SENSOR DE GAS DE ESCAPE (SENSOR DE OXIGENO ) 34 SENSOR DE CASCABELEO ( K.S. ) 35 SENSOR DE TEMPERATURA DE ENTRADA DE AIRE ( IAT ) 43 SENSOR DE POSICION DE LA MARIPOSA DE ACELERACION ( TPS ) 44 TODO EL SISTEMA FUNCIONA CORRECTAMENTE 45 FUGA EN INYECTORES 51 CIRCUITO ABIERTO EN INYECTOR 55 TODO EL SISTEMA FUNCIONA CORRECTAMENTE

PROCEDIMIENTO PARA BORRAR CODIGOS DE FALLA .

UNA VEZ INTERPRETADO LOS CODIGOS DE FALLA REALIZE NUEVAMENTE EL PUENTE DELCONECTOR DE DIAGNOSTICO CAVIDADES 6 Y 7 EN EL MOMENTO QUE SE ESTEN MOSTRANDOLOS CODIGOS DE FALLA.

NOTA: AL REALIZAR ESTE PROCEDIMIENTO EL FOCO DEBE PERMANECER APAGADOESPERE POR LO MENOS CINCO SEGUNDOS Y RETIRE EL PUENTE EL FOCO DEBERA QUEDARENCENDIDO INDICANDO QUE SE HAN BORRADO EN MEMORIA.DESACTIVE EL INTERRUPTOR DE ENCENDIDO A OFF.

PROCEDIMIENTO PARA BORRAR CODIGOS DE FALLA EN UN MOTOR 2 LITROS.1.- UNA VEZ INTERPRETADO LOS CODIGOS DE FALLA EN EL MOMENTO QUE SE ESTEN MOSTRANDO GIRE EL SELECTOR DE DIAGNOSTICO COMPLETAMENTE A LA DERECHA.2.- ESPERE POR LO MENOS CINCO SEGUNDOS Y REGRESE EL SELECTOR A SU POSICIONNORMAL.NOTA : AL REALIZAR ESTE PROCEDIMIENTO EL FOCO DE AVISO CHECK DEBERA QUEDARENCENDIDO.3.- DESACTIVAR EL INTERRUPTOR DE ENCENDIDO A OFF.

PROCEDIMIENTO DE AUTODIAGNOSTICO PARA UNIDADES PATHFINDER , ALTIMA, MAXIMA.MAXIMA VQ30DEINFINITI VQ30DEX TERRA VQ30DEQUEST VQ30DE300 ZX VQ30DE

PARA ENTRAR AL SISTEMA DE DIAGNOSTICO DE ESTAS UNIDADES LO PODEMOS REALIZAR SIN LA NECESIDAD DE UN MONITOR O APARATO DE DIAGNOSTICO. LA COMPUTADORA TRAE INTEGRADA UN SELECTOR DE DIAGNOSTICO EL CUAL NOS AYUDARA PARA OBTENER CODIGOS DE FALLA DEL SISTEMA.

EL PROCEDIMIENTO ES EL MISMO QUE EN UN MOTOR DE 2 LITROS CON LA DIFERENCIA QUE LOSDESTELLOS LENTOS EQUIVALEN A CENTENAS Y LOS RAPIDOS UNIDADES

NOTA : FOCO DE AVISO SERVICE ENGINE SOON

PASO 1.- ACTIVAR EL INTERRUPTOR DE ENCENDIDO A LA POSICION DE ON .NOTA: VERIFICAR QUE EL FOCO DE AVISO SERVICE ENGINE SOON.PASO 2 .- GIRE EL SELECTOR DE DIAGNOSTICO COMPLETAMENTE A LA DERECHA EN SENTIDO A LAS MANECILLAS DEL RELOJ ( HIGH ).

NOTA : AL REALIZAR ESTE PROCEDIMIENTO EL FOCO DE AVISO DE CHECK DEBE

APAGARSE.

PASO 3.- ESPERE POR LO MENOS CINCO SEGUNDOS Y REGRESE EL SELECTOR A SU POSICIONNORMAL ( LOW ) ES DECIR EN SENTIDO CONTRARIO A LAS MANECILLAS DEL RELOJ.

NOTA: AL REALIZAR ESTE PROCEDIMIENTO EL FOCO DE AVISO ENGINE SOON COMENZARA ADESTELLAR MOSTRANDO LOS CODIGOS EN MEMORIA.

SISTEMA DE ADMISION

UNIDAD DE CONTROL DE MARCHA MINIMA

FUNCION .- SE ENCARGA DE CONTROLAR LA MARCHA MINIMA DEL MOTOR , COMPENSAR LASCARGAS ADICIONALES QUE SUFRA EL MOTOR Y AMORTIGUAR LA DESACELERACION.

ESTA UNIDAD DE CONTROL DE MARCHA MINIMA SE INTEGRA DE LOS SIGUIENTES COMPONENTES :

VALVULA AUXILIAR DE CONTROL DE AIRE (VALVULA DE MARCHA MINIMA ) V.A.A.C.DISPOSITIVO DE CONTROL DE MARCHA MINIMA RAPIDA (FICD) Fast Idle Control DeviceTORNILLO DE AJUSTE DE MARCHA MINIMA

LOCALIZACION DE LA UNIDAD DE CONTROL DE MARCHA MINIMA.SE ENCUENTRA SUJETA EN EL MULTIPLE DE ADMISION DEL LADO CONTRARIO AL CUERPO DEACELERACION.

VALVULA AUXILIAR DE CONTROL DE AIRE

FUNCION : ES LA ENCARGADA DE CONTROLAR LA MARCHA MINIMA DEL MOTOR ,COMPENSA LAS CARGAS ADICIONALES QUE SUFRA Y AMORTIGUAR LA DESACELERACION. LA COMPUTADORA ATRAVEZ DE LA INFORMACION DE LOS SENSORESY ACTUADORES LA CONTROLA POR MEDIO DE UNA SEÑAL DE TIERRA . LA VALVULA ES CONTROLADA ATRAVEZ DE TIERRA LA CUAL SERA ENVIADA POR LA CAVIDAD 113 DE LA COMPUTADORA. ESTA SEÑAL ES VARIANTE DE ACUERDO A LA INFORMACION QUE ENVIEN LOS SENSORES E INTERRUPTORES

CODIGO DE FALLAEN LAS UNIDADES MEXICANAS NO TIENE SOLO EN VEHICULOS DE EXPORTACION CODIGO 205.

DISPOSITIVO DE CONTROL DE MARCHA MINIMA RAPIDA (FICD).

FUNCION

ES LA ENCARGADA DE COMPENSAR LA CARGA QUE SUFRE EL MOTOR AL MOMENTO DE ENTRAR EN FUNCIONAMIENTO EL SISTEMA DE AIRE CONDICONADO Y LO HACE PERMITIENDO LA ENTRADA DE AIRE ADICIONAL AL MULTIPLE DE ADMISION.LA VALVULA NO GENERA CODIGO DE FALLA YA QUE NO ES CONTROLADA DIRECTAMENTEPOR LA COMPUTADORA.

NOTA : VALVULA NORMALMENTE CERRADA.

SENSOR DE FLUJO DE MASA DE AIRE (MAF)

FUNCION

SE ENCARGA DE MEDIR LA CANTIDAD DE AIRE QUE ENTRA AL MOTOR Y SE LO INDICA A LA COMPUTADORA ATRAVEZ DE UNA SEÑAL DE VOLTAJE VARIABLE DE RETORNO CON ESTA INFORMACION LA COMPUTADORA CONTROLARA LA RELACION DE MEZCLA AIRE COMBUSTIBLE, TIEMPO DE ENCENDIDO Y EN LA ACTIVACION DEL SISTEMA EGR.

LOCALIZACION

EN LA GRAN MAYORIA DE LOS MOTORES NISSAN SE ENCUENTRA SUJETO EN EL PURIFICADOR DEAIRE CON EXCEPCION DE LOS MOTORES GA16DNE Y KA24E QUE SE ENCUENTRAN SUJETO ALCUERPO DE ACELERACION.

CODIGO DE FALLA 12

SENSOR DE POSICION DE MARIPOSA DE ACELERACION (TPS)

FUNCION

ES EL ENCARGADO DE INDICARLE A LA COMPUTADORA LA POSICION DE LA MARIPOSA DE ACELERACION ATRAVEZ DE UNA SEÑAL DE VOLTAJE VARIABLE.ESTA INFORMACION ES UTILIZADA PARA EL CONTROL OPTIMO DE LA RELACION DE MEZCLA AIRE COMBUSTIBLE, TIEMPO DE ENCENDIDO Y EN LA ACTIVACION DEL SISTEMA EGRLA FUNCION DE LA VALVULA EGR ES RECIRCULAR LOS GASES DE LA COMBUSTION .

TIPO DE SENSORES UN POTENCIOMETRO DE RESISTENCIA VARIABLE.

LOCALIZACION

SE ENCUENTRA SUJETO AL CUERPO DE ACELERACION Y TENDRA MOVIMIENTO ATRAVEZ DEL EJE DE LA MARIPOSA DE ACELERACION.VALORES DE LA SEÑAL DEL SENSOR DE POSICION DE LA MARIPOSA DE ACELERACION1.- CON MARIPOSA TOTALMENTE CERRADA SEÑAL DE .500 MAS MENOS .050 VOLTS.2.- ESTA SEÑAL DEBERA DE INCREMENTARSE PROGRESIVAMENTE CONFORME LA MARIPOSA SE ABRA HASTA LLEGAR A TENER 4.0 A 4.3 VOLTS.

NOTA : EN LAS UNIDADES CON MOTOR KA24E,GA16DNE ESTAS SEÑALES DEBERAN DE CHECARSE A TEMPERATURA NORMAL DE FUNCIONAMIENTO AL IGUAL EN EL MOMENTO DE CLAIBRARSE TODOS LOS SENSORES TPS EN NISSAN SON AJUSTABLES.

CODIGO DE FALLA 43

FALLAS DEL SENSOR TPS.

MOTOR ACELERADOPERDIDA DE POTENCIA AL DESPLAZARSE PROVOCANDO TIRONEOS O JALONEOSPROBLEMAS CON EL TIEMPO DE ENCENDIDOCONSUMO EXCESIVO DE COMBUSTIBLE LO QUE PROVOCA HUMO NEGRO Y ALTAS EMISIONES CONTAMINANTES.

SENSOR DE TEMPERATURA DE ENTRADA DE AIRE ( IAT )

FUNCION

SE ENCARGA DE MEDIR LA TEMPERATURA QUE ENTRA HACIA EL MOTOR. LA COMPUTADORA RECIBIRA ESTA INFORMACION ATRAVEZ DE UNA CAIDA DE VOLTAJE LA CUAL VARIA DE ACUERDO A LA TEMPERATURA EN FUNCION.

Temperature sensorThe temperature sensor plays a vital role in the ECCS system. Its function is to monitor coolant temperature and relay this information to the ECM. If it is cold the ECM will enrich the fuel mixture for startup for example.

LOCALIZACION

SE ENCUENTRA SUJETO EN EL PURIFICADOR DE AIRE.

TIPO DE SENSOR

ES UN TERMISTOR DE COEFICIENTE NEGATIVO ES DECIR , QUE LA RESISTENCIA VARIA DE ACUERDO A LA TEMPERATURA POR EJEMPLO A MAYOR TEMPERATURA MENOR RESISTENCIA.CODIGO DE FALLA 41

VALORES DE RESISTENCIA DEL SENSOR IATA 20 GRADOS CENTIGRADOS LA RESISTENCIA SERA DE 2100 A 2900 OHMSA 50 GRADOS CENTIGRADOS LA RESISTENCIA ES DE 680 A 1000 OHMSNOTA : AL FALLAR ESTE SENSOR SE GENERA EL CODIGO DE FALLA SOLO LO TRAEN LA PICK UP Y EL SR20DE.

SISTEMA DE CONTROL DE TEMPERATURA

COMPONENTES QUE INTEGRAN EL SISTEMA :

1.- E.C.U2.- SENSOR ECT3.- RELEVADORES DEL MOTOVENTILADOR.4.- MOTO VENTILADORES.5.- INTERRUPTOR TERMICO ( SOLO GA 16DE EQUIPADO

SENSOR ECT

LOCALIZACION

SE ENCUENTRA EN LOS DUCTOS DEL REFRIGERANTE DEL MULTIPLE DE ADMISION PARA UNIDADES CON MOTOR E16E Y SE LOCALIZA DEBAJO DEL DISTRIBUIDOR, EN LAS UNIDADES CON MOTOR GA16DE SE ENCUENTRA A UN LADO DE LA TAPA DEL MOTOR EN LA PARTE INFERIOR( CABLES CAFE Y ROJO CAFE ES TIERRA CONTROLADA Y ROJO ES CORRIENTE ).

FUNCION

INDICA A LA COMPUTADORA LA TEMPERATURA DEL REFRIGERANTE DEL MOTOR. LA SEÑAL DE ESTE SENSOR ES DETERMINANTE PARA QUE EL E.C.U. ACTIVE O DESACTIVE A LOS SIGUIENTES SISTEMAS :1.- RELACION DE MEZCLA AIRE COMBUSTIBLE2.- TIEMPO DE ENCENDIDO3.- ACTIVACION Y DESACTIVACION DE LOS MOTOVENTILADORES4.- SENSOR DE OXIGENO5.- DESACTIVACION DEL AIRE ACONDICIONADO6.- CONTROL DE LA VALVULA DE LA MARCHA MINIMA

TIPO DE SENSOR

ES UN TERMISTOR DE COEFICIENTE TERMICO NEGATIVO; ES DECIR QUE SU RESISTENCIA VARIA DE ACUERDO A LA TEMPERATURA. CUENTA CON UN CONECTOR DE DOS TERMINALES EN LAS CUALES VA A RECIBIR UNA SEÑAL DE 5 VOLTS QUE PROVIENE

DE LA CAVIDAD 18 DEL E.C.U. Y UNA SEÑAL DE TIERRA DE LA CAVIDAD 21 Y 29. DEPENDIENDO DE LA TEMPERATURA DEL MOTOR EL SENSOR TIENE UNA CAIDA DE VOLTAJE POR LA MISMA LINEA QUE RECIBE LOS 5 VOLTS.

VALORES DE RESISTENCIA

GRADOS CENTRIGADOS OHMS MOTOR20 DE 2700 A 2300 E16E 20 DE 2900 A 2100 50 DE 1000 A 680 80 DE 330 A 300 90 DE 260 A 230NOTA : LA RESISTENCIA CON EL MOTOR DE TEMPERATURA AMBIENTE REGISTRA ALREDEDOR DE 2900 OHMS PERO CONFORME SE VA CALENTANDO LA VALVULA DE CONTROL DE MARCHA MINIMA VA DANDO UNA CAIDA DE RESISTENCIA ESTO ES QUE DICHO COMPONENTE ESTA EN BUEN ESTADO.EL CABLE ROJO ES EL DE 5 VOLTS Y CUENTA CON 3.7 VOLTS APROXIMADAMENTE Y CONFORME VA SUBIENDO LA TEMPERATURA DEL MOTOR VA BAJANDO EL VOLTAJE HASTA LLEGAR A 0.50 VOLTS EL CAFE ES DE TIERRA CONTROLADA POR LA E.C.U.

FALLAS DEL SENSOR ECT

1.- PERDIDA DE POTENCIA AL DESPLAZARSE PROVOCANDO JALONEOS Y TIRONEOS.2.- CONSUMO EXCESIVO DE COMBUSTIBLE LO QUE PROVOCA HUMO NEGRO; ALTAS EMISIONES CONTAMINANTES,. AHOGAMIENTO DEL MOTOR.3.- INESTABILIDAD DEL MOTOR.ASI COMO EXPLOSIONES POR EL ESCAPE PUDIENDO SER LA CAUSA UN ADELANTO DE TIERRA CONTROLADA POR EL E.C.U. .AL DESCONECTAR ESTE SENSOR CON EL MOTOR FUNCIONANDO LOS VENTILADORES DEBEN DE ACTIVARSE, EN CASO DE QUE NO SE ACTIVEN VERIFICAR LAS ALIMENTACIONES AL RELAY Y COMPUTADORA, SI LAS ALIMENTACIONES ESTAN EN BUENAS CONDICIONES EL E.C.U. NO SIRVE POR LO QUE DEBERA REMPLAZARSE O ARREGLARLO AL FINAL DEL MANUAL LE INDICAREMOS DONDE HACEN ESOS TRABAJOS AUNQUE EN NISSAN ES MEJOR CAMBIAR EL E.C.U. POR LO CARO DE LA REPARACION DE 700 A 1000 PESOS APROXIMADAMENTE Y SI SE DAÑO EL CHIP PRINCIPAL MEJOR CAMBIE EL E.C.U.LA SEÑAL DEL SENSOR ECT INFLUYE EN EL CONTROL DEL TIEMPO , ADELANTANDOLO CUANDO ESTE DETECTE MOTOR FRIO. CONFORME SE CALIENTA EL MOTOR CON LA INFORMACION DEL ECT EL E.C.U. ATRASA EL TIEMPO DE ENCENDIDO HASTA QUEDAR EN LO ESPECIFICADO A LA TEMPERATURA NORMAL DE OPERACION.

REGULADOR DE AIRE PARA MOTOR EN FRIO

FUNCION :

PERMITIR LA ENTRADA DE AIRE ADICIONAL HACIA EL MULTIPLE DE ADMISION APROXIMADAMENTE DURANTE LOS PRIMEROS CINCO MINUTOS LO QUE DURA EN CALENTARSE EL MOTOR. EN SU INTERIOR UTILIZA UN BIMETALICO EL CUAL POR MEDIO DE TEMPERATURA CERRARA EL CONDUCTO DE ENTRADA DE AIRE.

ESTA TEMPERATURA LA RECIBIRA POR MEDIO DE UNA RESISTENCIA PRECALENTADORA Y DEL REFRIGERANTE DEL MOTOR.

LOCALIZACION :

SE ENCUENTRA SUJETO EN EL MULTIPLE DE ADMISION SOBRE UNOS CONDUCTOS DEREFRIGERANTE EL CUAL POR MEDIO DE RADIACION LE PROPORCIONA TEMPERATURA.

CONDICIONES DE ACTIVACION DE LOS MOTOVENTILADORES

1.- POR TEMPERATURA UNA VEZ QUE EL SENSOR ECT DETECTE EL VOLTAJE ADECUADO EN LA CAVIDAD 18.2.- CUANDO SE DESCONECTE EL SENSOR ECT.3.- CUANDO SE ACTUVE EL SISTEMA DE AIRE ACONDICIONADO.

LOCALIZACIONSE ENCUENTRA EN LA CAJA DE RELEVADORES QUE SE UBICA JUNTO A LA BATERIA COLOR AZUL .

SENSOR DE OXIGENO

FUNCION

SE ENCARGA DE MEDIR LA CANTIDAD DE OXIGENO QUE SE ENCUENTRA EN LOS GASES DEESCAPE Y SE LO INFORMA A LA UNIDAD DE CONTROL ELECTRONICA ATRAVEZ DE UNA SEÑALDE VOLTAJE LA CUAL VARIA SEGUN LA CANTIDAD DE OXIGENO QUE DETECTE.EN SU INTERIOR UTILIZA UNA CERAMICA DE SINCRONIA LA CUAL AL OBTENER SU TEMPERATURA DE FUNCIONAMIENTO COMENZARA A REACCIONAR DE TAL MANERA QUE LA COMPUTADORA SE ENTERE DEL OXIGENO QUE SE ENCUENTRAN EN LOS GASES DE ESCAPE.

LOCALIZACION

SE ENCUENTRA SUJETO EN EL MULTIPLE DE ESCAPE A ESTE SENSOR LO PODEMOS ENCONTRAR CON UNA Y TRES LINEAS ESTE ULTIMO TRAERA INTEGRADO UNA RESISTENCIA PRECALENTADORA.

TIPO DE SENSOR

ES UN GENERADOR DE VOLTAJE ES DECIR , QUE NO REQUIERE DE ALIMENTACIONES PARAENVIAR LA SEÑAL A LA CAVIDAD 19.

CODIGO DE FALLA33

VALORES DE LA SEÑAL DEL SENSOR DE OXIGENOESTA SEÑAL VARIA DE ACUERDO A LA RELACION DE MEZCLA AIRE COMBUSTIBLE.PRIMERA CONDICIONMEZCLA RICA SEÑAL MAYOR A 450 MILIVOTSSEGUNDA CONDICIONMEZCLA IDEAL SEÑAL DE 450 MILIVOLTSTERCERA CONDICIONMEZCLA POBRE SEÑAL MENOR DE 450 MILIVOLTS.NCONDICIONES PARA VERIFICAR LA SEÑAL DE OXIGENOPRIMERA CONDICIONLA COMPUTADORA NO DEBERA DE REGISTRAR NINGUN CODIGO DE FALLA.SEGUNDA CONDICIONTODO EL SISTEMA Y PARTE MECANICA DEBERA DE ENCONTRARSE EN PERFECTAS CONDICIONES.TERCERA CONDICIONMOTOR A TEMPERATURA NORMAL DE FUNCIONAMIENTO.CUARTA CONDICIONMOTOR A 2000 RPMNOTA : ESTA SEÑAL DEBERA VARIAR POR LO MENOS CINCO VECES EN 10 SEGUNDOS.

SENSOR DE VELOCIDAD DEL VEHICULO

DENTRO DE LAS UNIDADES NISSAN SE MANEJAN DOS TIPOS DE SENSORES GENERADORE INTERRUPTORESTE ULTIMO FUE EL PRIMERO EN UTILIZARSE DENTRO DE LAS UNIDADES NISSAN.

FUNCION

SE ENCARGA DE REGISTRAR LA VELOCIDAD DE LA UNIDAD E INFORMARSELO A LA UNIDAD DE CONTROL ELECTRONICA PARA EL CONTROL DE LA RELACION DE MEZCLA AIRE COMBUSTIBLE EN ALTA VELOCIDAD EN LA ACTIVACION DEL SISTEMA EGR , EN LA VALVULA SOLENOIDE DE ENCLAVAMIENTO DE LA TRANSMISION AUTOMATICA.LOCALIZACION DEL SENSOR TIPO INTERRUPTORSE ENCONTRARA DENTRO DEL TABLERO JUNTO AL VELOCIMETRO Y TENDRA MOVIMIENTO ATRAS DEL CHICOTE DEL VELOCIMETRO.

TIPO GENERADOR

ES UTILIZADO EN LA GRAN MAYORIA DE LAS UNIDADES NISSAN Y SE ENCUENTRA EN LA CAJA DE VELOCIDADES DE LA UNIDAD.

NOTA :AL UTILIZAR ESTE SENSOR NO TRAERA CHICOTE DE VELOCIDAD ATRAVEZ DE ESTA SEÑAL EL VELOCIMETRO FUNCIONARA.CODIGO DE FALLA 14

INTERRUPTOR PSPS

ES EL ENCARGADO DE INDICARLE A LA COMPUTADORA EL MOMENTO EN QUE SE APLICA LA DIRECCION HIDRAULICA Y LO HARA ATRAVEZ DE UNA CAIDA DE VOLTAJE. ESTA INFORMACION SE UTILIZA PARA COMPENSAR LA CARGA QUE SUFRA EL MOTOR.

LOCALIZACIONSE ENCUENTRA SUJETO EN LA LINEA DE ACEITE DE ALTA PRESION DE LA DIRECCION HIDRAULICA.

NOTA :ESTE INTERRUPTOR NO GENERA NINGUN CODIGO DE FALLA Y ES NORMALMENTE ABIERTO.FALLAS : SI TODO EL TIEMPO PERMANECE CERRADO EL MOTOR ESTARA ACELERADO, SI ESTA TODO EL TIEMPO ABIERTO EL MOTOR ESTARA INESTABLE.INTERRUPTOR NEUTRAL O INHIBIDORES INHIBIDOR EN TRANSMISION AUTOMATICA.ES INTERRUPTOR NEUTRAL EN TRANSMISON MANUAL.

FUNCION

INDICARLE A LA UNIDAD DE CONTROL ELECTRONICO EL MOMENTO EN EL QUE SE LE APLICA VELOCIDAD A LA UNIDAD Y ATRAVEZ DE ESTA INFORMACION COMPENSAR LA CARGA QUE SUFRA EL MOTOR ATRAVEZ DE LA VALCULA DE MARCHA MINIMA.

LOCALIZACIONSUJETO EN LA TRANSMISION DE LA UNIDAD.

NOTA :

NO GENERA CODIGO DE FALLA Y ES NORMALMENTE CERRADA.FALLAS.

SI PERMANECE TODO EL TIEMPO CERRADO EL MOTO PRESENTARA INESTABILIDAD AL MOMENTO DE METER VELOCIDAD.SI PERMANECE ABIERTO TODO EL TIEMPO EL MOTOR PERMANECERA ACELERADO

SISTEMA DE RECIRCULACION DE GASES DE ESCAPE

LA FINALIDAD DE RECIRCULAR LOS GASES DE ESCAPE HACIA LAS CAMARAS DE

COMBUSTION ES DISMINUIR LA TEMPERATURA PARA EVITAR LA FORMACION EN ALTAS CANTIDADES DE LOS OXIDOS DE NITROGENO YA QUE ES CONSIDERADO COMO EL QUINTO GAS.AL RECIRCULAR EL GAS DE ESCAPE HACIA LA CAMARA DE COMBUSTION SE EMPOBRECELA MEZCLA DE AIRE Y COMBUSTIBLE PROVOCANDO QUE LA DETONACION DISMINUYA SU FUERZA.CONDICIONES DE ACTIVACION DEL SISTEMA EGR Y PURGA DE CANISTER.PRIMERA CONDICIONMOTOR A TEMPERATURA NORMALSEGUNDA CONDICIONLA UNIDAD DEBERA DE DESPLAZARSE A UNA VELOCIDAD CRUCEROTERCERA CONDICIONEL MOTOR DEBERA ENCONTRARSE ARRIBA DE LAS 2000 RPMESTE COMPONENTE NO FUNCIONARA EN LOS SIGUIENTES CASOS :CUANDO EL MOTOR SE ENCUENTRE FRIOCUANDO EL MOTOR ESTE A ALTAS REVOLUCIONESCUANDO EL MOTOR SE ECHE A ANDAR.

Este circuito es muy sencillo, de pocos componentes y fácil de entender, protegerá nuestro automóvil de los amantes de lo ajeno. Con este circuito, una persona no autorizada no podrá arrancar nuestro automóvil para llevárselo.

Funcionamiento del Inmovilizador para vehiculo

Para proteger nuestro automóvil, el circuito que se propone desabilita el sistema de ignición poniendo a tierra el sistema de platinos, para los autos antiguos o el captor o sensor en autos más modernos. En el circuito que se muestra se puede observar que el elemento principal es un relé de 12 voltios con dos o mas pares de contactos

Cuando la llave de arranque del auto da energía al sistema de ignición, se alimenta el relé que está en serie con un capacitor. El relé de activa debido a que el capacitor que está inicialmente descargado (OV entre sus terminales). La activación del relé cierra el contacto NO (normalmente abierto) RL/1, que está en paralelo con el capacitor y causa que este se autoenclave.

Este relé tiene otro contato NO RL/2 conectado al cable que va de los platinos o sensor en el distribuidor a la bobina de encendido. Cuando este contacto está cerrado, no llega ninguna señal a la bobina y por ende el auto no arranca.

Mientras el vehículo esté en esta situación un diodo LED estará encendido, indicado al dueño del mismo que el sistema inmovilizador está activo.

Para poder eliminar el sistema inmovilizador, bastará con presionar momentáneamente un interruptor normalmente abierto (desactivación).

Al presionar el interruptor, RL/1 se abre y el autoenclavamiento desaparece, se carga el capacitor C, el LED se apaga y se habilita RL/2, lográndose con esto que el sistema de ignición electrónico o el sistema de platinos se habiliten.

Nota: Es importante que el interruptor de "desactivación" se encuentre en un lugar dentro del auto, que sólo el dueño conozca y asì evitar sorpresas desagradables.

Lista de componentes del circuito

- 1 Relé de 12 voltios con dos pares de contactos de salida (RL1 y RL2)- 1 capacitor electrolítico de 1000 uF- 1 diodo LED común color rojo- 2 resistores: 1 de 1.2K, 1 de 540 ohmios- 1 interruptor normalmente cerrado (desactivación)

Ya que en estas tierras guerrerenses es un tanto canijo no verse en problemas a causa de la delincuencia, les aporto este tip para que por lo menos no se lleven sus carros, si es que no tiene alarmas o bien para reforzar su sistema de seguridad!

http://www.unicrom.com/Tut_resistencia.asp

http://www.unicrom.com/Tut_diodo_led.asp

http://www.unicrom.com/Tut_capacitor-electrolitico.asp

http://www.unicrom.com/Tut_relay.asp

*el cable del switch es uno que solo tiene corriente al dar el ultimo paso y solo da korriente mientras prende el carro ya que lo ubicaron traten de cortarlo lo mas abajko posible donde sea dificil de encontrar en caso de que alguein quiera echarlo a andar puenteando los cables.1.-la parte del cable que se corta que viene de la llave va a la pata 87 del relay y la otra parte que va hacia la marcha va en la pata 30.2.-la pata 85 va a corriente directa de 12 volts esa pata siempre tendra corriente3.-la pata 86 va a un extremo del switch tipo valet del que tienen las alarmas (un boton pequeño) y el otro extremo del switch pa a tierra (el swtich debe quedar escondido donde solo tu sepas)

* en el dibujo queda bastante claro y ojala les sirva digo a mi me a ayudado mucho con mis compas que siemrpe quieren agarrar mi carro y nomas no pueden prenderlo

Relays / Starter Interrupts

Starter Interrupts:• Normally Closed Starter Kill Relay• Normally Open Starter Kill Relay• Passive Starter Kill Diagrams (3)

http://www.the12volt.com/relays/page2.asp#psk

http://www.the12volt.com/relays/page2.asp#sk2


Relays:• Converting Polarity• Starter Interrupts• Door Locks• Illuminated Entry & Light Flash• Special Applications• Relay Diagrams - Quick Reference

Car Security:• Basic Connections• Car Alarm Modules• Car Alarm Sensors / Triggers• Light Flash / Illuminated Entry• Starter Interrupts• Accessories & Add-ons

Normally Closed Starter Kill Relay

The basic starter kill relay diagram shown below, breaks continuity of the wire from the ignition switch to the starter motor (or in some cases i.e.; Ford, to another relay), when the alarm is armed and the ignition is turned on. This is the most commonly used application for disabling the starter. Click here for another starter kill diagram.

Normally Open Starter Kill

This normally open starter kill relay application below relies on a ground from the alarm when disarmed and 12 volts (+) from the ignition to enable the


http://www.the12volt.com/carsecurity/page6.asp

http://www.the12volt.com/relays/page2.asp





http://www.the12volt.com/relays/relaydiagrams.asp



http://www.the12volt.com/doorlocks/doorlocks.asp



driver to start the vehicle. * Note: most alarms with this feature will not provide this grounded output when power ,12 volts (+), to the alarm is not present, even if the alarm is grounded.

Passive Starter Kill

This is a stand alone starter kill. It does not rely on an alarm or keyless entry for it to work, only a simple momentary contact switch (normally open) to deactivate it. Every time the ignition is turned off, continuity is broken on the starter feed wire. To disable (or start), turn ignition on, then press the hidden switch, then start as normal.

You can substitute the switch with a number of others devices such as the amp turn on wire of your head unit. Be sure to isolate it with at least a 1 amp

diode. Turn the key to the run position. Allow the head unit to come on or turn it on. Now start the vehicle. If you connected to the power antenna wire, makesure the tuner is on. If you have a pullout or detachable face head unit, your vehicle will not start without it.

If you wish to use a device such as your horn, but do not want the horn to sound when you deactivate the starter kill, yet still work when driving, you canuse the same configuration above on both the horn and the starter wire as shown below. The starter kill is deactivated by the positive output of the vehicle's horn relay and the horn's interrupt is deactivated by the positive output of the starter wire from the key. You could substitute the horn with other devices such as parking lights, brake lights, etc. where you do not want it to be obvious that you used the device to disable the starter kill.

Que tal compañeros, en un rato de ocio me puse a diseñar esta conexion de Cortador de corriente de corte extraseguro, de echo si lo cortan tendras que reconectar todo para poder arrancar el auto.

Necesitaran primero que nada tener alarma, ya se After o la de agencia, con la after esta indicada una conexión mas segura que requiere un canal auxiliar disponible para desactivar el corte de corriente.

Material:1 relays Normalmente cerrado 3 Normalmente abiertos o en su defecto 4 que den las dos funciones.

1 Fusible de 10A con portafusible; su instalacion no esta indicada pero se pone en la entrada de la linea positiva de los 4 relays.Tanto cable como requiera el lugar de instalación.

Recomendaciones: 1.- Usar cable de un solo color o por mucho de 2 para no dar pauta a indentificación de polaridades.2.- Hacer el corte de corriente al positivo de la bomba de gasolina y ubicar la instalación oculta debajo de los asientos traseros.3.- Para los que no tienen el control integrado a la llave ya sea after o de

agencia. Traer el control de la alrma aparte de las llaves, asi si te llegan a bajar solo accionas el panico, entrara el cortador de corriente y aunque desactiven laalarma y se desactive su cortador integrado, el nuevo cortador seguira inmobilizando el auto.

Este Cortador de corriente es seguro ya que cuando se acciona hay total ausencia de corriente en relays, de esta forma no consume bateria al estar activo de echo lo hace al estar desactivo con autoenclave de relays y si cortan la llegada de corriente a los relays pues simplemente no se cerrara el circuito.

Cabe aclarar que ningun sistema es infalible, pero entre mas asegures el auto mas tiempo le tomara al ladron el poder eliminar los sistemas para poder llevarselo al grado de desistir.

Les dejo el diagrama

Les dejo el diagrama con la conexion real de los relays y el diagrama de controlk electrico!3.- Invertir el orden de los relays que puse en los diagramas, marcar un relay con barniz como el 1 y la indicación del rsto hacerlo en un papel y guardarlo con el instructivo de la alarma para futurs referencias.

solenoide de control del turbo. -...

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