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. The title of the lamp describes the usage of the lamp.
- Low oil pressure lamp
- High coolant temperature lamp
- Low coolant level lamp
- Maintenance indicator lamp
- Diagnostic lamp
- Warning lamp
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| Illustration 1 | g00885205 |
Schematic | |
Test Step 1. Inspect Electrical Connectors and Wiring
- Turn the keyswitch OFF.
- Thoroughly inspect the J3/P3 customer connector, the J1/P1 ECM connector, and the J2/P2 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 suspect lamp. Refer to Illustration 1.
- Check the J3/P3 customer connector (allen head screw) for the proper torque of 2.25 ± 0.25 N·m (20 ± 2 lb in).
Check the ECM connector J1/P1 and J2/P2 for the proper torque of 2.25 N·m (20 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.
- Monitor the suspect lamp.
Expected Result:
The lamp should turn on for 5 seconds. Then, the lamp should turn off.
Results:
- OK - The lamp appears to be operating correctly at this time. Stop.
- Not OK - Proceed to Test Step 3.
Test Step 3. Measure the Voltage at the Lamp Socket
- Turn the keyswitch ON.
- Measure the voltage at the lamp socket.
Expected Result:
The voltage should be between 12.0 VDC and 24.0 VDC.
Results:
- OK - The voltage is between 12.0 VDC and 24.0 VDC.
Repair: Replace the bulb.Verify that the repair eliminates the problem.
Stop.
- Not OK - The voltage is not in the range that is expected. Proceed to Test Step 5.
Test Step 4. Test the Individual Lamp Circuits
- Disconnect the J1/P1 ECM connector.
- Insert a 40-Pin Breakout T between the J1 ECM connector and the 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 socket for the driver for the suspect lamp.
- Insert the other end of the jumper wire into the socket for negative battery or +battery as required. Refer to Table 1 for the appropriate pin locations in order to check the individual circuits.
Show/hide table
Table 1 Indicator Lamp J1/P1 Driver Jumper Low coolant level P1:27 P1:23 Low oil pressure P1:21 P1:23 High coolant temperature P1:22 P1:23 Maintenance indicator P1:28 P1:5 Diagnostic lamp P1:40 P1:5 Warning lamp P1:34 P1:5
- Turn the keyswitch to the ON position and observe the lamp.
Expected Result:
The suspect lamp turns on while the jumper is connected to both sockets. Also, the suspect lamp turns off when the jumper is removed from one of the sockets.
Results:
- OK - The circuit for the 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.
Repair: Repair the lamp circuit.Verify that the repair eliminated the problem.
Stop.
Test Step 5. Check the Voltage at the ECM
- Disconnect the J1/P1 ECM connector.
- Insert a 40-Pin Breakout T between the J1 ECM connector and the P1 ECM connector.
- Measure the voltage between the sockets that are shown in Table 2.
| ECM Voltage | |
| +Battery | -Battery |
| P1:4 | P1:5 |
| P1:6 | P1:5 |
Expected Result:
The voltage is between 12.0 VDC and 24.0 VDC.
Results:
- OK - The ECM is operating correctly. There is a problem in the wiring or the lamp. Repair the wiring or the lamp, as required. Verify that the repair eliminates the problem. Stop.
- Not OK - Temporarily connect a test ECM. Check the operation of the diagnostic lamp 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. Stop.