The following indicator lamps are used to inform the operator of various occurrences that are taking place with the engine. Use the test steps if the lamp does not operate correctly.
- Low oil pressure lamp
- High coolant temperature lamp
- Maintenance indicator lamp
- Diagnostic lamp
- Warning lamp
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| Illustration 1 | g00949707 |
Schematic | |
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| Illustration 2 | g00949757 |
P1 ECM connector | |
Test Step 1. Inspect Electrical Connectors and Wiring
- Turn the keyswitch to the OFF position.
- Thoroughly inspect the J61/P61 customer connector, and the J1/P1 ECM connector. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
- Perform a 45 N (10 lb) pull test on each of the wires in the customer connector and the ECM connector that are associated with the indicator lamps.
- Check the J61/P61 customer connector (allen head screw) for the proper torque of 2.25 ± 0.25 N·m (20 ± 2 lb in).
Check the J1/P1 ECM connector for the proper torque of 6.0 N·m (55 lb in).
- Check the harness and wiring for abrasions and for pinch points from the battery to the ECM.
Results:
- OK - Proceed to Test Step 2.
- Not OK -
Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem.
Stop.
Test Step 2. Check for Normal Operation of the Lamp
- Turn the keyswitch to the ON position and monitor the indicator lamps.
Expected Result:
The lamp should turn on for 5 seconds. Then, the lamp should turn off.
Results:
- OK - The indicator lamps appear to be operating correctly at this time.
Repair: If an intermittent problem is suspected, refer to Troubleshooting, "Electrical Connectors - Inspect".
Stop.
- Not OK - The indicator lamps are not operating correctly. Proceed to Test Step 3.
Test Step 3. Measure the Voltage at the Lamp Socket
- Use a test lamp to check for voltage at the suspect lamp socket within the first five seconds after the keyswitch is turned ON.
Expected Result:
The test lamp should illuminate during the first five seconds after the keyswitch is turned ON.
Results:
- OK - The test lamp illuminated.
Repair: Replace the bulb.Verify that the repair eliminates the problem.
Stop.
- Not OK - The test lamp did not illuminate. Proceed to Test Step 4.
Test Step 4. Test the Individual Lamp Circuits
- Disconnect the J1/P1 ECM connector.
- Fabricate a jumper wire 100 mm (4 inch) long. Crimp a Deutsch pin to both ends of the wire.
- Insert one end of the jumper wire into the terminal for the suspect lamp in the P1 ECM connector.
- Insert the other end of the jumper wire into the terminal in the P1 ECM connector for the negative battery or the +Battery as required.
Note: Refer to Table 1 for the appropriate terminal locations in the P1 ECM connector.
Show/hide tableTable 1 Indicator Lamp Lamp Jumper Low oil pressure P1:28 P1:61 High coolant temperature P1:29 P1:61 Maintenance indicator P1:21 P1:70 Diagnostic lamp P1:19 P1:70 Warning lamp P1:20 P1:70
- Turn the keyswitch to the ON position and observe the lamp.
- Remove the jumper wire and observe the lamp.
Expected Result:
The indicator lamp turns on while the jumper is connected to both terminals. Also, the indicator lamp turns off when the jumper is removed.
Results:
- OK - The circuit for the indicator lamp is functioning properly. Proceed to Test Step 5.
- Not OK - The lamp did not turn on. The lamp circuit is not functioning properly. There is a problem in the wiring between the lamp and the ECM and/or between the lamp and the battery.
Repair: Repair the lamp circuit.Verify that the repair eliminated the problem.
Stop.
Test Step 5. Check the Voltage at the ECM
- Install a breakout T at the J1/P1 ECM connector.
- Install a test lamp between the terminals in the breakout T for the suspect lamp.
Note: Refer to Table 2 for the appropriate terminal locations in the breakout T.
Show/hide tableTable 2 Indicator Lamp Lamp Jumper Low oil pressure P1:28 P1:61 High coolant temperature P1:29 P1:61 Maintenance indicator P1:21 P1:70 Diagnostic lamp P1:19 P1:70 Warning lamp P1:20 P1:70
- Turn the keyswitch to the ON position and monitor the test lamp.
Expected Result:
The test lamp should turn on for 5 seconds. Then, the test lamp should turn off.
Results:
- OK - The ECM is operating correctly. There is a problem in the wiring or the lamp.
Repair: Repair the wiring or the lamp, as required.Verify that the repair eliminates the problem.
Stop.
- Not OK - The ECM does not appear to be functioning properly.
Repair: Temporarily connect a test ECM. Check the operation of the indicator lamps when the test ECM is installed. If the problem is resolved with the test ECM, then reconnect the suspect ECM. If the problem returns with the suspect ECM, then replace the ECM. Refer to Troubleshooting, "Replacing the ECM".
Stop.