The Analog Sensor Supply provides power to all analog sensors.
The Electronic Control Module (ECM) supplies 5.0 ± 0.2 VDC from the ECM connector J1/P1 to each analog sensor connector. The sensor return line connects to the ECM connector J1/P1.
The analog sensor supply is output short circuit protected. A short circuit to the battery will not damage the circuit inside the ECM.
Note: The analog sensors are not protected from overvoltage. Directly connecting the analog sensor to battery voltage can result in damage. If the CID-FMI 262-03 is logged, it is possible that all of the analog sensors have been damaged. This engine contains two electronic control modules. Be sure that you perform the test procedure for the correct ECM. The MID for the primary ECM is 036. The MID for the secondary ECM is 047.
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| Illustration 1 | g00621489 |
Primary ECM | |
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| Illustration 2 | g00621419 |
Secondary ECM | |
Test Step 1. Check for Connector Damage.
- Turn the circuit breaker for the battery to the OFF position.
- Turn the ECS to the OFF/RESET position.
- Check all of the connectors and wiring for the following problems: damage, corrosion, abrasion and incorrect attachment.
Expected Result:
The connectors and wiring should be free of the following problems: damage, corrosion, abrasion and incorrect attachment.
Results:
- OK - The connectors and wiring are free of problems. Proceed to test step 2.
- Not OK - The connectors and wiring are not free of problems.
Repair: Repair the connectors and/or wiring or replace the connectors and/or wiring.
Stop.
Test Step 2. Check the Harness for Shorts.
- Disconnect ECM connector J1/P1. Disconnect all of the analog sensors.
- Measure the resistance between the analog supply P1-36 and the analog return P1-30.
- Measure the resistance between the analog supply P1-36 and the engine ground.
- Measure the resistance between the analog return P1-30 and the engine ground.
Expected Result:
Resistance should be more than 20,000 Ohms for each measurement.
Results:
- OK - Resistance is greater than 20,000 Ohms for each measurement. Proceed to test step 3.
- Not OK - Resistance is less than 20,000 Ohms for each measurement.
Repair: Repair the connectors and/or wiring or replace the connectors and/or wiring.
Stop.
Test Step 3. Check Analog Sensor Supply Voltage.
- Reconnect ECM connector J1/P1.
- Turn the circuit breaker for the battery to the ON position.
- Turn the ECS to the STOP position.
- Measure the voltage between the analog supply P1-36 and the analog return P1-30.
Expected Result:
The supply voltage should be 5.0 ± 0.2 VDC.
Results:
- OK - The Analog Sensor Supply is producing the correct voltage. Proceed to test step 4.
- Not OK - Check that the ECM is receiving the correct voltage from the battery.
Repair: Perform a diagnostic functional test. Perform the diagnostic functional test Troubleshooting, "Electrical Power Supply".
Stop.
Test Step 4. Check Analog Sensor Supply Voltage.
- Measure the voltage between socket A and socket B on the harness side of all analog sensor connectors.
Expected Result:
The supply voltage should be 5.0 ± 0.2 VDC.
Results:
- OK - Supply voltage is reaching all analog sensor connectors. Proceed to test step 5.
- Not OK - There is an open circuit in the harness or connectors.
Repair: Repair the connectors and/or wiring or replace the connectors and/or wiring.
Stop.
Test Step 5. Check Analog Sensors for Shorts.
- Connect the analog sensor. Check the voltage between socket A and socket B of the sensor. Repeat this step for all of the analog sensors.
- Turn the ECS to the OFF/RESET position.
Expected Result:
The supply voltage should be 5.0 ± 0.2 VDC after each analog sensor is connected.
Results:
- OK - The analog sensor supply and the harness are OK.
Repair: The repair is complete.
Stop.
- Not OK - The voltage is OK before the sensor is connected. The voltage is NOT OK after the sensor is connected. The sensor may be internally shorted.
Repair: Temporarily replace the sensor. Verify that the new sensor solves the problem before you permanently install the new sensor. Calibrate the new sensor.
Stop.