950K and 962K Wheel Loaders Electrohydraulic System Caterpillar

Illustration 1	g02677078
Connections of the Quick Coupler Disengage solenoid

This diagnostic code is associated with the Quick Coupler Disengage solenoid. The FMI 03 diagnostic code is activated when the ECM detects an above normal voltage of the solenoid circuit.

The following conditions could cause this diagnostic code to be activated:

• The energize circuit of the solenoid is shorted to another voltage source.

• The ECM has failed. This condition is unlikely.

Note: Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, that all connections are secure and that all connections are in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure.

Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected.

Test Step 1. CHECK THE ENERGIZE CIRCUIT OF THE SOLENOID FOR A SHORT

1. Turn the disconnect switch and the key start switch to the OFF position.

2. Disconnect the machine harness connector from the solenoid. Disconnect the machine harness connectors J1 and J2 from the ECM.

3. At the machine harness connectors for the ECM, measure the resistance from contact J2-3 (wire 780-PU(Purple)) to all of the other contacts that are used in the J1 and J2 connectors for the ECM.

Expected Result:

Each resistance measurement is greater than 5000 ohms.

Results:

• YES - Each resistance measurement is greater than 5000 ohms. The resistance measurement does not indicate a short in the machine harness. Proceed to Test Step 2.

• NO - Each resistance measurement is not greater than 5000 ohms. There is a short in the machine harness.

  Repair: The short is between wire 780-PU(Purple) and the circuit that has a low resistance measurement.

  For information on testing for short circuits and finding short circuits, refer to Testing and Adjusting, "Wiring Harness (Short Circuit) - Test". Repair the machine harness or replace the machine harness.

  STOP

Test Step 2. CHECK THE OPERATION OF THE ECM

The disconnect switch and the key start switch remain in the OFF position. The machine harness connectors for the solenoid and the ECM remain disconnected.

1. At the machine harness connector J2 for the ECM, use a 151-6320 Removal Tool to remove the solenoid wire 780-PU(Purple) and the socket at contact J2-3 from the harness connector.

2. Reconnect the machine harness J1 and J2 connectors to the ECM.

3. Turn the disconnect switch and the key start switch to the ON position.

4. Observe the status of the active CID 2815 FMI 03 diagnostic code.

Expected Result:

The CID 2815 FMI 03 diagnostic code is no longer active. A CID 2815 FMI 05 diagnostic code is now active.

Results:

• YES - The CID 2815 FMI 03 diagnostic code is no longer active. A CID 2815 FMI 05 diagnostic code has become active after the solenoid circuit is disconnected. The ECM has responded correctly to the open circuit condition in the solenoid circuit. Reconnect the solenoid wire in the ECM connector before proceeding to the next step. Proceed to Test Step 3.

• NO - The CID 2815 FMI 03 diagnostic code remains active. The status of the active diagnostic code was not changed even when the solenoid wire was disconnected from the ECM.

  Repair: The ECM has not responded correctly to the open condition in the solenoid circuit. The operation of the ECM is not correct.

  Prior to replacing an ECM, always contact the Technical Communicator at your dealership for possible consultation with Caterpillar. This consultation may effect repair time. If the ECM must be replaced, refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".

  STOP

Test Step 3. CHECK THE STATUS OF THE DIAGNOSTIC CODE

1. Inspect the harness connectors. Clean the contacts of the harness connectors. Check the wires for damage to the insulation that is caused by excessive heat, battery acid, or chafing.

2. Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit.

3. Reconnect all harness connectors. Make sure that the connectors are fully seated. Observe that the clips for each connector are fastened.

4. Turn the disconnect switch and the key start switch to the ON position.

5. Operate the machine.

6. Determine if the CID 2815 FMI 03 diagnostic code is active.

Expected Result:

The CID CID 2815 FMI 03 diagnostic code is active.

Results:

• YES - The CID 2815 FMI 03 diagnostic code remains active.

  Repair: Check the circuit again. Perform a Wiggle Test on the machine wiring harness with the Caterpillar Electronic Technician (Cat ET) service tool. The Wiggle Test can detect the following in the machine wiring harness:

  • Momentary shorts

  • Intermittent shorts

  • Opens
  If the problem remains, the ECM may have failed. This condition is unlikely due to the following:

  • The ECM detected the open circuit condition in the solenoid circuit.

  • The ECM activated the FMI 05 diagnostic code when the wire that energizes the solenoid was disconnected.
  Verify that all possible causes of the diagnostic code have been investigated. Exit this procedure and perform this procedure again.

  Prior to replacing an ECM, always contact the Technical Communicator at your dealership for possible consultation with Caterpillar. This consultation may effect repair time. If the cause of the diagnostic code is not found and the ECM must be replaced, refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".

  STOP

• NO - The CID 2815 FMI 03 code is not active. The problem does not exist at this time.

  Repair: The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected. Resume normal machine operation.

  STOP