24M Motor Grader Power Train Electronic Control System MID 027 - CID 0679 - FMI 05 Caterpillar

Conditions Which Generate This Code:

Illustration 1	g02625575
Schematic of the Lockup Clutch Solenoid

The CID 0679 FMI 05 diagnostic code is associated with the Lockup Clutch Solenoid. The FMI 05 diagnostic code means that the ECM has detected that the current for the solenoid circuit is below normal.

The coil resistance for this solenoid is 8.7 ± 0.4 ohms at 25°C.

Conditions that cause this diagnostic code to be activated are listed below

• The energize circuit of the solenoid is open.

• The return circuit of the solenoid is open.

• The solenoid has failed.

• The ECM has failed. The failure of the ECM 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 SOLENOID

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

2. Disconnect the machine harness from the solenoid .

3. At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire 705-PK) to contact 2 (wire 921-WH).

4. Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.

5. Observe the status of the CID 0679 FMI 05 diagnostic code.

Expected Result:

The CID 0679 FMI 05 diagnostic code is no longer active. A CID 0679 FMI 06 diagnostic code becomes active when the jumper wire is connected.

Results:

• YES - The CID 0679 FMI 05 diagnostic code is no longer active. A CID 0679 FMI 06 diagnostic code becomes active when the jumper wire is connected. The solenoid has failed.

  Repair: Replace the solenoid. Verify that the new solenoid corrects the problem.

  STOP

• NO - The CID 0679 FMI 05 diagnostic code remains active. The jumper wire does not affect the status of the active diagnostic code. The solenoid is not the cause of the problem. Proceed to Test Step 2.

Test Step 2. CHECK THE CIRCUIT FOR AN OPEN

The jumper wire that was installed in the previous Test Step remains in place.

1. The key start switch and the battery disconnect switch remain in the OFF position.

2. Disconnect the machine harness ECM connector J1 from the ECM.

3. At the machine harness connector J1 for the ECM, measure the resistance from contact J1-48 (wire 705-PK) to contact J1-50 (wire 921-WH).

4. While observing the multimeter resistance measurement, wiggle the machine harness connectors for the ECM and wiggle the machine harness connector for the solenoid. Gently pull on the wires and move the wires around.

Expected Result:

The resistance measurement is less than 5.0 ohms at all times during the manipulation of the harness and connectors.

Results:

• OK - The resistance measurement is less than 5.0 ohms. The resistance measurement is not indicating an open or a bad connection in the circuit. Proceed to Test Step 3.

• NOT OK - The resistance measurement is greater than 5.0 ohms. The resistance measurement is indicating an open circuit or a bad connection in the machine harness.

  Repair: A resistance measurement that is greater than 5000 ohms could indicate that a wire is either not connected or is open. A resistance measurement that is greater than 5.0 ohms but less than 5000 ohms could indicate that one of the connection points in the circuit is not open but is not a good connection.The open or possible bad connection is in supply wire 705-PK or in return wire 921-WH of the machine harness. Refer to the complete machine Electrical System Schematic. Check all of the connectors that are in the solenoid circuit. Ensure that all connections are clean, secure and in good condition. Repair the machine harness or replace the machine harness.

  STOP

Test Step 3. CHECK THE OPERATION OF THE ECM.

The disconnect switch and the key start switch remain in the OFF position. The machine harness connector for the solenoid and the ECM J1 connector remain disconnected.

1. Remove the jumper wire that was installed in the last test step.

2. At the machine harness connector J1 for the ECM, use a 151-6320 Removal Tool to remove the solenoid energize wire 705-PK and socket at contact J1-48 from the harness connector.

3. Reconnect the machine harness J1 connector to the ECM.

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

5. Use a 7X-1710 Multimeter Probe that is not connected to a multimeter or a similar device to contact the ECM pin at J1-48 through the vacant space in the J1 connector.

6. While observing the status of the active CID 0679 FMI 05 diagnostic code, ground the other end of the 7X-1710 Multimeter Probe to frame ground.

Expected Result:

The CID 0679 FMI 05 diagnostic code is no longer active. A CID 0679 FMI 06 diagnostic code becomes active when the ECM pin at J1-48 is grounded.

Results:

• YES - The CID 0679 FMI 05 diagnostic code is no longer active. A CID 0679 FMI 06 diagnostic code has been activated after the ECM pin is grounded. The ECM has responded correctly to the grounded circuit condition in the solenoid circuit. The ECM is most likely not the cause of the problem.
  
  Reinstall the disconnected solenoid energize wire back into the correct spot in the ECM connector before proceeding to the next Test Step.
  
  Proceed to Test Step 4.

• NO - The CID 0679 FMI 05 diagnostic code remains active. The status of the active diagnostic code does not change when the ECM pin for the solenoid is grounded.

  Repair: The ECM has not responded correctly to the grounded condition in the solenoid circuit. The operation of the ECM is not correct.Prior to replacing an ECM, always contact your Technical Communicator for possible consultation with AVSpare. This consultation may greatly reduce repair time. If the ECM must be replaced, refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".

  STOP

Test Step 4. CHECK THE STATUS OF THE DIAGNOSTIC CODE

1. The key start switch and the battery disconnect switch remain in the OFF position.

2. 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, corrosion, or chafing.

3. Reconnect all harness connectors. Make sure that the connectors are fully seated and 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. Check the status of the CID 0679 FMI 05 diagnostic code.

Expected Result:

The CID 0679 FMI 05 diagnostic code is active.

Results:

• YES - The CID 0679 FMI 05 diagnostic code is active. The diagnostic code has not been corrected.

  Repair: Check the circuit again. Use the Cat Electronic Technician (ET) service tool to perform a "Wiggle Test" on the machine wiring harness. The wiggle test can detect momentary or intermittent shorts or opens in the machine wiring harness.If the cause of the problem is not found in the machine harness, the ECM may have failed. A failure of the ECM is unlikely as the ECM responded correctly to the grounded condition in the previous test step.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 your Technical Communicator for possible consultation with AVSpare. This consultation may greatly reduce repair time. If the cause of the active 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 0679 FMI 05 diagnostic code is not active. The diagnostic code does not exist at this time.

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

  STOP