Engine Mount Control Unit

DTC Troubleshooting: U0029, U0100 (Engine Mount Control Unit)

DTC U0029: F-CAN Malfunction (BUS-OFF)

DTC U0100: F-CAN Malfunction (Engine Mount Control Unit-PCM)

NOTE:

- Before you troubleshoot, record all freeze data and any on-board snapshots, and review the general troubleshooting information. Initial Inspection and Diagnostic Overview

- Information marked with an asterisk (*) applies to the CANL line.

1. Check the MIL on the gauge. MIL Circuit Troubleshooting

Does the MIL on?
YES - Go to the PGM-FI system's general troubleshooting information. Initial Inspection and Diagnostic Overview

NO - Go to step 2.


2. Turn the ignition switch to ON (II).

3. Clear the DTC with the HDS.

4. Check for Temporary DTCs or DTCs with the HDS.

Is DTC U0029 and/or U0100 indicated?
YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the engine mount control unit and the PCM.


5. Turn the ignition switch to LOCK (0).

6. Disconnect engine mount control unit 16P connector.

7. Measure the resistance between engine mount control unit 16P connector terminal No. 12* and No. 14.

Is there about 20 Ohms or more?
YES - Go to step 8.

NO - Repair short in the wire(s) between engine mount control unit 16P connector terminals No. 12* and No. 14, then go to step 13.






8. Check for continuity between engine mount control unit 16P connector terminal No. 14 (No. 12)* and body ground.

Is there continuity?
YES - Repair short to ground in the wire between engine mount control unit 16P connector terminal No. 14 (No. 12)* and body ground, then go to step 13.

NO - Go to step 9.






9. Jump the SCS line with the HDS.

10. Disconnect PCM connector A (49P).

11. Connect PCM connector terminal A48 (A49)* to body ground with the jumper wire.






12. Check for continuity between engine mount control unit 16P connector terminal No. 14 (No. 12)* and body ground.

Is there continuity?
YES - Check for poor connections or loose terminals at the engine mount control unit and the PCM. If it is OK, replace the engine mount control unit, Service and Repair then go to step 13.

NO - Repair open in the wire between engine mount control unit 16P connector terminal No. 14 (No. 12)* and the PCM connector terminal A48 (A49)*, then go to step 13.






13. Reconnect all connectors.

14. Turn the ignition switch to ON (II).

15. Clear the DTC with the HDS.

16. Check for Temporary DTCs or DTCs with the HDS.

Is DTC U0029 and/or U0100 indicated?
YES - Check for poor connections or loose terminals at the engine mount control unit and the PCM, then go to step 1.

NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.