966G Wheel Loader and 972G Wheel Loader Power Train Caterpillar

Harness code input is communicated from the Caterpillar Monitoring System to the power train electronic control module (ECM) via the CAT Data Link. The Caterpillar Monitoring System uses the harness code plug to select the appropriate machine configuration. The power train ECM receives the harness code input. The power train ECM also selects the appropriate machine configuration.

CID 0270 FMI 12 service code is recorded when the power train ECM receives harness code input from the Caterpillar Monitoring System that does not match any machines that are supported. The power train ECM will continue to operate by using the previous valid machine harness code.

The following causes could signal this fault:

• The wrong harness code plug is installed.

• The wrong harness code wire on the Caterpillar Monitoring System is open or shorted to ground.

• The wrong Caterpillar Monitoring System ECM is installed.

• The power train ECM is faulty. This is unlikely.

Note: If an incorrect harness code plug is connected to the Caterpillar Monitoring System, a CID 0650 FMI 12 may be recorded. Ensure that the CID 0650 FMI 12 is on hold. Also, ensure that the present indicator shows "SERV CODE" or that "SERV CODE" is shown in the diagnostic message screen of the Caterpillar Electronic Technician (ET).

1. Check the code of the monitoring system.

   1. Enter the harness code (Mode 1) of the Caterpillar Monitoring System.

   2. Check that the machine code matches the sales model. Refer to table 1 that follows for the machine codes.
      Show/hide table

      Table 1

      Machine Codes
      Sales Model	Machine Code
      950G	13
      962G	14
      IT62G	17
      966G	20
      972G	21

      Expected Result: The two-digit machine code that is shown should match the machine.

      Results:

      • OK - Monitoring machine code is correct. Proceed to Step 2.

      • NOT OK - Monitoring system harness code plug is not correct. Repair the harness code plug for the monitoring system or replace the harness code plug with the correct harness code plug. Refer to System Operation, Testing and Adjusting, SENR1394, "Caterpillar Monitoring System" for more information on the Caterpillar Monitoring System.

2. Check if the fault is still present.

   1. Turn the key start switch and the disconnect switch to the OFF position. Clean the contacts of the harness connectors.

   2. Reconnect all of the harness connectors.

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

   4. Enter the service mode (Mode 3) of the Caterpillar Monitoring System. Clear all inactive faults. The Caterpillar Electronic Technician (ET) may also be used to delete inactive faults.

   5. Operate the machine in all speeds and in all directions.

   6. Determine if the CID 0270 FMI 12 service code is present or if the fault is shown in the diagnostic message screen of the Caterpillar Electronic Technician (ET).

      Expected Result: The CID 0270 FMI 12 service code is not present.

      Results:

      • YES - The fault is no longer present. The initial fault was probably caused by a poor electrical connection or by a short at one of the harness connectors that was reconnected. Resume normal operation. STOP.

      • NO - The fault is still active. Either the machine harness has failed or the wrong machine monitoring system was installed. Repair the harness or the monitoring system. If necessary, replace the harness or the monitoring system.