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DTC Troubleshooting

DTC U1101: F-CAN Malfunction (PCM-ACM)

NOTE:
- Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.
- If DTC U0073 is stored at the same time as DTC U1101, troubleshoot DTC U0073 first, then recheck for DTC U1101.

1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Check for Temporary DTCs or DTCs with the HDS.

Is DTC U1101 indicated?

YES - Go to step 4.

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

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

Is DTC P15AB indicated?

YES - Go to step 5.

NO - Go to step 8.

5. Turn the ignition switch OFF.
6. Disconnect the engine mount control unit 20P connector.




7. Check for continuity between engine mount control unit 20P connector terminals No.5 and No.17*.

Is there continuity?

YES - Substitute a known-good engine mount control unit, then go to step 16 and recheck. If DTC U1101 is not indicated, replace the original engine mount control unit, then go to step 16.

NO - Repair open in the wire between the engine mount control unit (No.5 (No.17)*) and the PCM (A36 (A1) *), then go to step 16.

*: CANL line

8. Check for poor connections at the engine mount control unit 20P connector.

Are the connections OK?

YES - Go to step 9.

NO - Repair the connections, then go to step 16.

9. Turn the ignition switch OFF.
10. If not already done, disconnect the engine mount control unit 20P connector.
11. Turn the ignition switch ON (II).




12. Measure voltage between engine mount control unit 20P connector terminal No.4 and body ground.

Is there battery voltage?

YES - Go to step 13.

NO - Check the No.9 IG METER (10 A) fuse in the driver's under-dash fuse/relay box. If the fuse is OK, repair open in the wire between the No.9 IG METER (10 A) fuse and the engine mount control unit, then go to step 15.

13. Turn the ignition switch OFF.




14. Check for continuity between engine mount control unit 20P connector terminal No.14 and body ground.

Is there continuity?

YES - Substitute a known-good engine mount control unit, then go to step 16 and recheck. If DTC U1101 is not indicated, replace the original engine mount control unit, then go to step 16.

NO - Repair open in the wire between the engine mount control unit and G503, then go to step 15.

15. Turn the ignition switch OFF.
16. Reconnect the engine mount control unit 20P connector.
17. Turn the ignition switch ON (II).
18. Reset the PCM with the HDS.
19. Do the PCM idle learn procedure.
20. Check for Temporary DTCs or DTCs with the HDS.

Is DTC U1101 indicated?

YES - Check for poor connections or loose terminals at the gauge control module, 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 DTCs troubleshooting.