 | |
| Illustration 1 | g00762287 |
Schematic of the Cross Axle Differential Lock Solenoid Valve | |
This diagnostic code is recorded when the ECM reads the current of the solenoid as being below normal.
The possible causes for this diagnostic code are listed:
- The circuit of the solenoid is open.
- The return circuit of the solenoid is open.
- The solenoid has failed.
- The ECM has failed. This is unlikely.
Note: Ensure that the CID 1100 FMI 05 for the solenoid is on hold and that the "SERV CODE" indicator shows "SERV CODE". This procedure can cause new diagnostic codes to be recorded. Ignore these created diagnostic codes. When the procedure is completed, clear the created diagnostic codes.
Test Step 1. CHECK THE SOLENOID.
- Turn the disconnect switch and the key start switch to the ON position. Do not start the engine. Ensure that the diagnostic code for the solenoid is on hold and that the "SERV CODE" indicator is showing "SERV CODE".
- Disconnect the machine harness from the solenoid.
- At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire 368-OR) to contact 2 (wire K952-BR).
- Observe the status of the "SERV CODE" indicator.
Expected Result:
As the jumper wire is installed and removed, the "SERV CODE" will show and the "SERV CODE" will NOT show.
Results:
- YES - The circuit is correct. The solenoid has failed.
Repair: Repeat this test step "CHECK THE SOLENOID" in order to verify that the solenoid has failed. Replace the solenoid.
Stop.
- NO - The diagnostic code remains. Proceed to test step 2.
Test Step 2. CHECK THE HARNESS CIRCUITS FOR OPENS.
- Turn the key start switch and the disconnect switch to the OFF position.
- Disconnect the machine harness connectors J1 and J2 from the ECM.
- At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire 368-OR) to contact 2 (wire K952-BR).
- At the machine harness connector J1 and J2, measure the resistance from signal contact J2-25 (wire 368-OR) to J2-13 (wire K952-BR).
Expected Result:
The resistance that is measured is less than 5.0 ohms.
Results:
- OK - The resistance that is measured is less than 5.0 ohms. The machine harness is correct. Proceed to test step 3.
- NOT OK - The resistance is greater than 5.0 ohms. There is an open circuit in the machine harness.
Repair: The open is in wire (368-OR) or in the return wire (K952-BR) of the machine harness. Repair the harness or replace the harness.
Stop.
Test Step 3. CHECK IF THE DIAGNOSTIC CODE REMAINS.
- Inspect the contacts and clean the contacts of the harness connectors.
- Reconnect all harness connectors.
- Turn the disconnect switch and the key start switch to the ON position.
- Enter service mode of the Caterpillar Monitoring System and clear all inactive diagnostic codes.
- Operate the machine.
- Observe the status of the diagnostic code for the solenoid. The "SERV CODE" is NOT showing.
Expected Result:
The diagnostic code for the solenoid is NOT present. The "SERV CODE" is NOT showing.
Results:
- YES - The diagnostic code is NOT present. The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. Stop.
- NO - The diagnostic code has not been corrected. The ECM has failed.
Repair: It is unlikely that the ECM has failed. Exit this procedure and perform this diagnostic code procedure again. If the cause of the diagnostic code is not found, replace the ECM. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace".
Stop.