COVER 6G6688 - Caterpillar

Transmission ECM
The following is a list of Diagnostic Trouble Codes (DTCs) that are associated with the CAN data link of the machine.
Table 1
Transmission ECM (MID 81)
DTC Code Description System Response
871-9 Inclination Sensor: Abnormal update rate Automatic Retarding will not function.
3583-9 Switch Panel #1: Abnormal update rate Communication between the Transmission ECM and the Switch Panel will be intermittent or disabled.
967–9 Machine Application: Abnormal update rate. The features on this ECM may not run. Possible causes for an FMI 9 diagnostic code are:
The ECM has failed.
An ECM software problem.
A short circuit to ground or to another circuit.
An open or a poor connection in the Can Data Link circuits near the ECM.
One of the ECMs or smart devices has failed. This condition is unlikely.
Illustration 1 g03473237
Schematic of the CAN Data Link
Note: The diagram above is a simplified schematic of the Transmission ECM and the CAN Data Link connections. The schematic is electrically correct. However, not all of the possible harness connectors are shown. Refer to the latest revision for the complete schematic.Diagnostic Trouble Code Procedure
Note: Prior to beginning this procedure, inspect the harness connectors that are involved in this circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, secure, and in good condition. Check the wiring for pinch points or abrasions. Look for and repair areas that indicate wires are exposed. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing a troubleshooting procedure.
Table 2
Troubleshooting Test Steps Values Results
1. Identify The Active FMI Code Associated With The CAN Data Link
Code present. FMI 9 diagnostic code, proceed to Test Step 2.
Begin Process For FMI 9 Troubleshooting HERE
2. Check The Data Link For An Open
A. Turn the key switch and the battery disconnect switch to the OFF position.
B. Disconnect the machine harness connector from the ECM.
C. At the disconnected connector for the ECM, connect a jumper wire between CAN