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Mike S.
Mike S., Chevy Mechanic
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Experience:  ASE Certified Master Technician
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1995 chevy: injectors..the ecm,ignition module..oil pressure..sensors

Customer Question

i have a 1995 chevy with a freshly rebuilt 350 its in a k1500 at first i wasnt getting signal to turn on the fuel pump i found a ground unhooked then i was getting signal it ran for 5 minutes i stopped getting signal to the fuel pump again i ran a hot wire to it it ran for 20 minutes then stopped im not getting signal to it or my injectors to spray if u hook up the fuel pump to a hot it pumps if u hook up the injectors to hot and ground they spray im getting positive feed to injectors no signal from the wires coming from the ecm i changed the ecm,ignition module,oil pressure sender im getting oil pressure ignition module test good. what would keep me from getting signal still? what other sensors or whatever would cause this?
Submitted: 4 years ago.
Category: Chevy
Expert:  Mike S. replied 4 years ago.
I'm uploading a few wiring diagrams, give me 1 minute.
Expert:  Mike S. replied 4 years ago.

First thing is check the fuse I pointed to in this pic. Then check for voltage at the orange wire coming out of the underhood fuse relay center, then the orange wire at the fuel pump relay, then with key on run the gray wire coming out of the relay, if nothing there check for the relay being energized at the dark green\white wire at the relay, if ok there check the ground black\white wire at relay to ground.

graphic

Expert:  Mike S. replied 4 years ago.

If all ok there check the darkgreen\white wire coming out the PCM at F6.

Expert:  Mike S. replied 4 years ago.
You also have 2 fuses in the underhood fuse\relay center. The Eng-1 mini fuse 20 amp and the ECM-1 mini fuse 20 amp.
Mike S., Chevy Mechanic
Category: Chevy
Satisfied Customers: 5060
Experience: ASE Certified Master Technician
Mike S. and other Chevy Specialists are ready to help you
Customer: replied 4 years ago.
those fuses r good and im getting power to the orange wire, power to green and white, and power to the gray coming out of the box the gray coming out of the box i was running a jump wire from that to the pump to run the pump but injectors rnt getting signal from the computer the pink wire is getting constent power to the injectors
Expert:  Mike S. replied 4 years ago.

The gray wire does go to the fuel pump, so if you are having to jump from the gray wire to the pump then there is a break down the line further toward the pump. The pink wire to the injectors should only have voltage in the run and start position. Plus, the pink wire will have constant voltage with key on run or start, its the dark blue and dark green wires going to the pcm that actually control the injectors, the pink wire is just a power feed, the injectors are then open and closed by the pcm.

So, now when you turn the key to run, do you hear the fuel pump run for a few seconds? It will shut back off if you dont crank. So when you crank do you get fuel spray from injectors? I don't know if a test light will work on the dark grren and dark blue wires, I believe you will need a noid light in case the injectors are not spraying fuel to check, but you should be able to hear the injectors clicking when the key is turned to crank. If they click and you have fuel then the injectors are clogged. You may want to check the fuel pressure regulator to make sure you do have enough pressure to the injectors.

Expert:  Mike S. replied 4 years ago.

Ok, i did read where you said the injectors will spray, so they are not clogged. Then you will need a noid light to check those dark green and dark blue wires. I did just read an article on a homemade noid light but autozone sells a set for like $25.

Give me a few minutes and let me see a good way to make your own. I know you will need an led. Light emitting diode.

Customer: replied 4 years ago.
yea the pink wire gets power when the key is on i dont belive im getting the signal to the other wire from the pcm i did check continuity from each injector to the pcm and im getting a conection threw the wire. the gray wire from the relay is putting out power when its calling for fuel so i have a break in the line does that run stright back to my pump besides the split offs. that gray wire runs to my pcm to and im getting power back to that from it. could that wire not getting a connection have anything to do with my injectors? i appreciate ur help when i get home tonight im going to load some more cash on here for u. thanks
Expert:  Mike S. replied 4 years ago.
First of all it wouldn't be from the pcm, it would be to the pcm, the injectors are turned off and on by the pcm that is how they work. It seems the only problem that you found was the gray wire going to the pump, repair that. Then test the injectors, maybe the pcm will not allow the injectors to operate if there is no power to the fuel pump, but did you check the injectors while you were jumping the fuel pump, at the same time. Give me afew minutes I'll try to answer that question about the pcm.
Expert:  Mike S. replied 4 years ago.

In the meantime since I was already looking for a noid lite, I'll post what I found while I try to answer about the pcm.

It looks like I got conflicting stories on a noid lite. Some people say you can just use a voltmeter but it will be hard to read, others say you can use a 12 volt test light, and another says it has to be a 6 volt test light, so I figured I would just find the kit.

http://indoors.pricegrabber.com/mechanics-tools-tool-sets/Astro-Pneumatic-Deluxe-Noid-Lite-GM-Signal/m22593818.html/search=noid%20light/st=product/sv=title

Astro Pneumatic (AP 7898) Deluxe Noid Lite and GM Signal Test Light Set # XXXXX

Astro Pneumatic (AP 7898) Deluxe Noid Lite and GM Signal Test Light Set # XXXXX

MPN: 7898

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As low as $14.94 from Amazon Marketplace

Description: Also known as: AP 7898, AP7898, APT-7898, AST-7898, AST7898; Features and Benefits: The most economic way to check electronic fuel injection signals Quickly and easily checks for systems of GM TBI, Bosch PFI Ford TBI, GM PFI, Geo TBI and GM SCPI To test just disconnect the f... read more

 

http://www.noidlight.com/making-your-own-noid-light/

All you're going to need are the following materials: socket, bulb, and a 3.4W 12V bulb #158

Expert:  Mike S. replied 4 years ago.

This is all I found.

The electronic fuel injection system is a fuel metering system with the amount of fuel delivered by the Throttle Body Injectors (TBI) determined by an electronic signal supplied by the Electronic Control Module (ECM). The ECM monitors various engine and vehicle conditions to calculate the fuel delivery time (pulse width) of the injectors. The fuel pulse may be modified by the ECM to account for special operating conditions, such as cranking, cold starting, altitude, acceleration and deceleration.

The ECM controls the exhaust emissions by modifying fuel delivery to achieve, as near as possible, an air/fuel ratio of 14.7:1. The injector "on" time is determined by various inputs to the ECM. By increasing the injector pulse, more fuel is delivered, enriching the air/fuel ratio. Decreasing the injector pulse, leans the air/fuel ratio.

The basic TBI unit is made up of two major casting assemblies: (1) a throttle body with a valve to control airflow and (2) a fuel body assembly with an integral pressure regulator and fuel injector to supply the required fuel. An electronically operated device to control the idle speed and a device to provide information regarding throttle valve position are included as part of the TBI unit.

The fuel injector is a solenoid-operated device controlled by the ECM. The incoming fuel is directed to the lower end of the injector assembly which has a fine screen filter surrounding the injector inlet. The ECM actuates the solenoid, which lifts a normally closed ball valve off a seat. The fuel under pressure is injected in a conical spray pattern at the walls of the throttle body bore above the throttle valve. The excess fuel passes through a pressure regulator before being returned to the vehicle fuel tank.

The pressure regulator is a diaphragm-operated relief valve with injector pressure on one side and air cleaner pressure on the other. The function of the regulator is to maintain a constant pressure drop across the injector throughout the operating load and speed range of the engine.

The throttle body portion of the TBI may contain ports located at, above, or below the throttle valve. These ports generate the vacuum signals for the EGR valve, MAP sensor and the canister purge system.

 

Go ahead and fix that gray wire, than it may work or then jump those darkgreen and darkblue to ground. But I believe it will work as soon as the ecm or pcm reads that the fuel pump is supplying pressure. Let me know!

 

 

http://www.autozone.com/autozone/repairinfo/repairguide/repairGuideContent.jsp?chapterTitle=Throttle+Body+Injection++Tbi&partName=Fuel+Systems&pageId=0900c1528008f2b6&subChapterTitle=General+Information&partId=0900c1528008f1e6

 

Customer: replied 4 years ago.
i fixed the gray wire to the fuel pump it works right know but the injectors still arnt working if u jump the green and blue wires that go to the injectors to a ground they spray would a oxygen sensor have anything to do with it i cant think of anything else
Expert:  Mike S. replied 4 years ago.
To my knowledge an O2 sensor only comes into affect in closed loop, since you cant get it started and warmed up enough to go from open loop to closed, I dont really think that has anything to do with it. Have you checked all the fuses and relays and fusible links?
Customer: replied 4 years ago.
yea as far as i know the fuel pump relay is all working fuel pump is working properly im getting power to 1 side of each injector which is the pink wire im getting power to my ecm at the ignition wire and the battery wire im getting power to my egr solienoid and the purge canister i believe there called i think i checked everything besides the ignition module and oil pressure switch what else tells the ecm to tell the injectors to squirt?
Expert:  Mike S. replied 4 years ago.
The pcm should at least allow the fuel injectors to run in failsafe mode even with a sensor bad. Where did you get that new ecm? Was it new or off like ebay? Are the numbers on it exactly the same? Did anyone program it for your vehicle? I am going to upload a few tests for the TPS, the Crank sensor, coolant sensor, mass air flow sensor, map sensor, and intake temp sensor but like I said the ecm should at least run in safe mode. Did you check for codes, recently even after fixing fuel pump problem?
Expert:  Mike S. replied 4 years ago.

No pictures showed up, here download from my site.

http://mysite.verizon.net/res12a0uo/sitebuildercontent/sitebuilderfiles/no_injector_pulse.doc

 

Operation

The Throttle Position Sensor (TPS) is connected to the throttle shaft on the throttle body. It is a potentiometer with one end connected to 5 volts from the ECM and the other to ground.

A third wire is connected to the ECM to measure the voltage from the TPS. As the throttle valve angle is changed (accelerator pedal moved), the output of the TPS also changes. At a closed throttle position, the output of the TPS is low (approximately .5 volts). As the throttle valve opens, the output increases so that, at wide-open throttle, the output voltage should be approximately 4.5 volts.

By monitoring the output voltage from the TPS, the ECM can determine fuel delivery based on throttle valve angle (driver demand).

Testing

1. Backprobe with a high impedance voltmeter at TPS terminals A and B.

2. With the key ON and engine off, the voltmeter reading should be approximately 5.0 volts.

3. If the voltage is not as specified, either the wiring to the TPS or the ECM may be faulty. Correct any wiring or ECM faults before continuing test.

4. Backprobe with a high impedance voltmeter at terminals C and B.

5. With the key ON and engine off and the throttle closed, the TPS voltage should be approximately 0.5-1.2 volts.

6. Verify that the TPS voltage increases or decreases smoothly as the throttle is opened or closed. Make sure to open and close the throttle very slowly in order to detect any abnormalities in the TPS voltage reading.

7. If the sensor voltage is not as specified, replace the sensor.

Throttle Position Sensor (TPS)

 

Crankshaft Position Sensor

The Crankshaft Position (CKP) Sensor provides a signal through the ignition module which the ECM uses as a reference to calculate rpm and crankshaft position. The Crankshaft Position (CKP) sensor is a hall-effect type sensor that monitors crankshaft position and speed. There are four teeth 90° apart on the front crankshaft sprocket that induce a pulse in the sensor which is transmitted to the ECM.

Testing

Animations and Tech Tips


Click to view: TPS voltage sweep

1. Disconnect the CKP sensor harness. Connect an LED test light between battery ground and CKP harness terminal A.

2. With the ignition ON and the engine off, verify that the test light illuminates.

3. If not as specified, repair or replace the fuse and/or wiring.

4. Carefully connect the test light between CKP harness terminal A and B. Verify that the test light illuminates.

Crankshaft Position (CKP) sensor wiring diagram

Click to Enlarge

5. If not as specified, repair the CKP harness ground circuit (terminal B).

6. Turn the ignition OFF and disconnect the test light.

7. Next, connect suitable jumper wires between the CKP sensor and CKP sensor harness. Connect a duty cycle meter to the jumper wire corresponding to CKP terminal C and battery ground.

8. Crank the engine and verify that the duty cycle signal is between 40-60%.

9. If it is not as specified, the CKP sensor may be faulty.

10. Next, connect a AC volt meter to the jumper wire corresponding to CKP terminal C and battery ground.

11. Crank the engine and verify that the AC voltage signal is at least 10.0 volts.

12. If not as specified the CKP sensor may be faulty.

1. Check the sensor wiring, the wiring harness and the terminals for damage and repair as necessary.

2. Disconnect the CKP sensor harness. Connect an Digital Volt Ohm Meter (DVOM) attach the negative lead of the meter to battery ground and the positive lead to CKP harness terminal C. The voltage should be between 4.8-5.2 volts.

3. If not as specified, repair or replace the fuse and/or wiring.

4. Connect an LED test light between the battery positive terminal and CKP terminal B.

5. With the ignition ON and the engine off, verify that the test light illuminates.

6. If not as specified, repair or replace the wiring.

Crankshaft Position (CKP) sensor wiring diagram-6.5L diesel engine

Click to Enlarge

7. Turn the ignition OFF and disconnect the test light.

8. Next, connect suitable jumper wires between the CKP sensor and CKP sensor harness. Connect a DVOM to the jumper wire corresponding to CKP terminal A and battery ground.

9. Crank the engine and verify that the voltage is 4 volts or more.

10. If it is not as specified, the CKP sensor may be faulty.

Coolant Temperature Sensor

The coolant temperature sender changes resistance as the coolant temperature increases and decreases.

The coolant temperature sensor is a thermistor (a resistor which changes value based on temperature). Low coolant temperatures produce high resistance (100,000 ohms at -40°F/-40°C) while low temperatures causes low resistance (70 ohms at 266°F/130°C). The sensor is mounted in the coolant stream and the ECM supplies a 5 volt signal to the sensor through a resistor in the ECM and measures the voltage. The voltage will be high when the engine is cold, and low when the engine is hot. By measuring the voltage, the ECM knows the engine coolant temperature.

The Engine Coolant Temperature (ECT) sensor is mounted in the intake manifold and sends engine temperature information to the ECM. The ECM supplies 5 volts to the coolant temperature sensor circuit. The sensor is a thermistor which changes internal resistance as temperature changes. When the sensor is cold (internal resistance high), the ECM monitors a high signal voltage which it interprets as a cold engine. As the sensor warms (internal resistance low), the ECM monitors a low signal voltage which it interprets as warm engine.

Engine Coolant Temperature (ECT) sensor location-4.3L, 5.0L and 5.7L engines

The coolant temperature sensor is a thermistor (a resistor which changes value based on temperature). Low coolant temperatures produce high resistance (100,000 ohms at -40°F/-40°C) while low temperatures causes low resistance (70 ohms at 266°F/130°C). The sensor is mounted in the coolant stream and the ECM supplies a 5 volt signal to the sensor through a resistor in the ECM and measures the voltage. The voltage will be high when the engine is cold, and low when the engine is hot. By measuring the voltage, the ECM knows the engine coolant temperature effects most systems the ECM controls.

Testing

Animations and Tech Tips


Click to view: Testing an ECT sensor

1. Check the instrument cluster fuse condition and replace as necessary.

2. Check the sender wire for damage and repair as necessary.

3. Unplug the sender electrical connection.

4. Attach one end of a jumper wire to the sender electrical connector and the other end of the jumper wire to ground.

5. If the gauge functions properly, replace the sender.

1. Remove the sensor from the vehicle.

2. Immerse the tip of the sensor in container of water.

3. Connect a digital ohmmeter to the two terminals of the sensor.

4. Using a calibrated thermometer, compare the resistance of the sensor to the temperature of the water. Refer to the engine coolant sensor temperature vs. resistance illustration.

5. Repeat the test at two other temperature points, heating or cooling the water as necessary.

6. If the sensor does not meet specification, it must be replaced.

Submerge the end of the coolant temperature sensor in cold or hot water and check the resistance

Click to Enlarge

 

Coolant temperature sensor wiring diagram

Click to Enlarge

 

Coolant temperature sensor temperature vs. resistance values

Click to Enlarge

1. Remove the ECT sensor from the vehicle.

2. Immerse the tip of the sensor in container of water.

3. Connect a digital ohmmeter to the two terminals of the sensor.

4. Using a calibrated thermometer, compare the resistance of the sensor to the temperature of the water. Refer to the engine coolant sensor temperature vs. resistance illustration.

5. Repeat the test at two other temperature points, heating or cooling the water as necessary.

6. If the sensor does not met specification shown in the temperature versus resistance chart, it must be replaced.

7. The sensor may also be checked in the vehicle. Unplug the sensor and attach a digital ohmmeter to the two terminals of the sensor.

8. Using a calibrated thermometer, compare the resistance of the sensor to the ambient air temperature.

9. Repeat the test at two other temperature points, heating or cooling the water as necessary.

10. If the sensor does not met specification shown in the temperature versus resistance chart, it must be replaced.

The ECT sensor is usually located near the thermostat housing

Click to Enlarge

 

Using a thermometer, a DVOM and some jumper leads, check the resistance of the ECT sensor and compare your readings to those in the chart

Click to Enlarge

 

Submerge the end of the coolant temperature sensor in cold or hot water and check the resistance

Click to Enlarge

 

Engine Coolant Temperature (ECT) sensor wiring diagram

Click to Enlarge

 

Engine Coolant Temperature (ECT) sensor temperature vs. resistance values

Click to Enlarge

 

Mass Air Flow Sensor

The Mass Air Flow (MAF) Sensor measures the amount of air entering the engine during a given time. The ECM uses the mass airflow information for fuel delivery calculations. A large quantity of air entering the engine indicates an acceleration or high load situation, while a small quantity of air indicates deceleration or idle.

Exploded view of the Mass Air Flow (MAF) sensor

Testing

Animations and Tech Tips


Click to view: A dirty airflow sensor

1. Backprobe with a high impedance voltmeter between MAF sensor terminals C and B.

2. With the ignition ON engine off, verify that battery voltage is present.

3. If the voltage is not as specified, either the wiring to the MAF sensor, fuse or the ECM may be faulty. Correct any wiring or ECM faults before continuing test.

4. Disconnect the voltmeter and backprobe with a frequency meter between MAF sensor terminals A and B.

5. Start the engine and wait until it reaches normal idle speed and verify that the MAF sensor output is approximately 2000 Hz.

6. Slowly raise engine speed up to maximum recommended rpm and verify that the MAF sensor output rises smoothly to approximately 8000 Hz.

7. If MAF sensor output is not as specified the sensor may be faulty.

Mass Air Flow (MAF) sensor wiring diagram

Click to Enlarge

 

Manifold Absolute Pressure (MAP) sensor

Operation

The Manifold Absolute Pressure (MAP) sensor measures the changes in intake manifold pressure, which result from the engine load and speed changes, and converts this to a voltage output.

A closed throttle on engine coastdown will produce a low MAP output, while a wide-open throttle will produce a high output. This high output is produced because the pressure inside the manifold is the same as outside the manifold, so 100 percent of the outside air pressure is measured.

The MAP sensor reading is the opposite of what you would measure on a vacuum gauge. When manifold pressure is high, vacuum is low. The MAP sensor is also used to measure barometric pressure under certain conditions, which allows the ECM to automatically adjust for different altitudes.

The ECM sends a 5 volt reference signal to the MAP sensor. As the manifold pressure changes, the electrical resistance of the sensor also changes. By monitoring the sensor output voltage, the ECM knows the the manifold pressure. A higher pressure, low vacuum (high voltage) requires more fuel, while a lower pressure, higher vacuum (low voltage) requires less fuel.

The ECM uses the MAP sensor to control fuel delivery and ignition timing.

 

Testing

Animations and Tech Tips


Click to view: Testing a MAP sensor

1. Backprobe with a high impedance voltmeter at MAP sensor terminals A and C.

2. With the key ON and engine off, the voltmeter reading should be approximately 5.0 volts.

3. If the voltage is not as specified, either the wiring to the MAP sensor or the ECM may be faulty. Correct any wiring or ECM faults before continuing test.

4. Backprobe with a high impotence voltmeter at MAP sensor terminals B and A.

5. Verify that the sensor voltage is approximately 0.5 volts with the engine not running.

6. Start the vehicle.

7. Verify that the sensor voltage is greater than 1.5 volts at idle.

8. Verify that the sensor voltage increases to approximately 4.5. volts at Wide Open Throttle (WOT).

9. If the sensor voltage is as specified, the sensor is functioning properly.

10. If the sensor voltage is not as specified, check the sensor and the sensor vacuum source for a leak or a restriction. If no leaks or restrictions are found, the sensor may be defective and should be replaced.

Manifold Absolute Pressure (MAP) Sensor wiring diagram

Click to Enlarge

1. Backprobe with a high impedance voltmeter at MAP sensor terminals A and C.

2. With the key ON and engine off, the voltmeter reading should be approximately 5.0 volts.

3. If the voltage is not as specified, either the wiring to the MAP sensor or the ECM may be faulty. Correct any wiring or ECM faults before continuing test.

4. Backprobe with the high impotence voltmeter at MAP sensor terminals B and A.

5. Verify that the sensor voltage is approximately 0.5 volts with the engine not running (at sea level).

6. Record MAP sensor voltage with the key ON and engine off.

7. Start the vehicle.

8. Verify that the sensor voltage is greater than 1.5 volts (above the recorded reading) at idle.

9. Verify that the sensor voltage increases to approximately 4.5. volts (above the recorded reading) at Wide Open Throttle (WOT).

10. If the sensor voltage is as specified, the sensor is functioning properly.

11. If the sensor voltage is not as specified, check the sensor and the sensor vacuum source for a leak or a restriction. If no leaks or restrictions are found, the sensor may be defective and should be replaced.

Location of the MAP sensor-TBI system shown

Click to Enlarge

 

Probe the terminals of the MAP sensor to check for proper reference voltage

Click to Enlarge

 

Manifold Absolute Pressure (MAP) sensor wiring diagram

Click to Enlarge

 

Intake Air Temperature Sensor

Operation

the Intake Air Temperature (IAT) Sensor is a thermistor which changes value based on the temperature of the air entering the engine. Low temperature produces a high resistance, while a high temperature causes a low resistance. The ECM supplies a 5 volt signal to the sensor through a resistor in the ECM and measures the voltage. The voltage will be high when the incoming air is cold, and low when the air is hot. By measuring the voltage, the ECM calculates the incoming air temperature.

the IAT sensor signal is used to adjust spark timing according to incoming air density.

Intake Air Temperature (IAT) sensor

Click to Enlarge

Testing

1. Remove the Intake Air Temperature (IAT) sensor.

2. Connect a digital ohmmeter to the two terminals of the sensor.

3. Using a calibrated thermometer, compare the resistance of the sensor to the temperature of the ambient air. Refer to the temperature vs. resistance illustration.

4. Repeat the test at two other temperature points, heating or cooling the air as necessary with a hair dryer or other suitable tool.

5. If the sensor does not meet specification, it must be replaced.

Intake Air Temperature (IAT) sensor wiring diagram

Click to Enlarge

6.

Intake Air Temperature (IAT) sensor temperature vs. resistance values

Click to Enlarge

www.chiltononline.com

Customer: replied 4 years ago.
i didnt get it programed i pulled it from a junk yard but the numbers matched and the prom numbers matched. does it need to be programed?
Expert:  Mike S. replied 4 years ago.
Probably not since both numbers are the same. Have you tested any of the sensors yet?
Customer: replied 4 years ago.

no im on the road till tomorow as soon as i get there im testing them does that have a crank poistion sensor some one told me it didnt

 

Expert:  Mike S. replied 4 years ago.

I believe it does, I got the testing procedure for it.

Crankshaft Position Sensor

1995 Chevrolet Truck K1500 1/2ton P/U 4WD 5.7L TBI 8cyl

The Crankshaft Position Sensor is located:

Under hood, center, front engine area, rear of crankshaft pulley, mounted in engine block

GM Full-Size Trucks 1988-1998 Repair Information

Crankshaft Position (CKP) Sensor

 

OPERATION



See Figure 1

The Crankshaft Position (CKP) Sensor provides a signal through the ignition module which the ECM uses as a reference to calculate rpm and crankshaft position.



Click image to see an enlarged view

Fig. Fig. 1: Crankshaft Position (CKP) sensor

TESTING



See Figure 2

  1. Disconnect the CKP sensor harness. Connect an LED test light between battery ground and CKP harness terminal A.
  2. With the ignition ON and the engine off, verify that the test light illuminates.
  3. If not as specified, repair or replace the fuse and/or wiring.
  4. Carefully connect the test light between CKP harness terminal A and B. Verify that the test light illuminates.




Click image to see an enlarged view

Fig. Fig. 2: Crankshaft Position (CKP) sensor wiring diagram

  1. If not as specified, repair the CKP harness ground circuit (terminal B).
  2. Turn the ignition OFF and disconnect the test light.
  3. Next, connect suitable jumper wires between the CKP sensor and CKP sensor harness. Connect a duty cycle meter to the jumper wire corresponding to CKP terminal C and battery ground.
  4. Crank the engine and verify that the duty cycle signal is between 40-60%.
  5. If it is not as specified, the CKP sensor may be faulty.
  6. Next, connect a AC volt meter to the jumper wire corresponding to CKP terminal C and battery ground.
  7. Crank the engine and verify that the AC voltage signal is at least 10.0 volts.
  8. If not as specified the CKP sensor may be faulty.

 

 

 

http://www.autozone.com/autozone/repairinfo/componentlocations/componentLocationMain.jsp?fromSearchPage=true&categoryNValue=4294963514&categoryName=Crankshaft+Position+Sensor

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