DTC Troubleshooting

DTC U0122: F-CAN Malfunction (PCM-VSA Modulator-Control Unit)

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 U0122, troubleshoot DTC U0073 first, then recheck forDTCU0122.

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 U0122 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 VSA modulator-control unit and the PCM.

4. Check for a DTC in the DTCs MENU with the HDS.

Is VSA DTC 86 indicated?

YES - Go to step 5.

NO - Go to step 8.

5. Turn the ignition switch OFF.
6. Disconnect the VSA modulator-control unit 47P connector.




7. Check for continuity between VSA modulator-control unit 47P connector terminals No.14 and No.30*.

Is there continuity?

YES - Substitute a known-good VSA modulator-control unit, then go to step 15 and recheck. If DTC U0122 is not indicated, replace the original VSA modulator-control unit, then go to step 15.

NO - Repair open in the wire between the VSA modulator-control unit (No.14 (No.30)*) and the PCM (A36 (A1)*), then go to step 15.

*: CANL line

8. Check for poor connections at the left engine compartment wire harness/dashboard wire harness 20P connector.

Are the connections OK?

YES - Go to step 9.

NO - Repair the connections, then go step 15.

9. Turn the ignition switch OFF.
10. If not already done, disconnect the VSA modulator-control unit 47P connector.
11. Turn the ignition switch ON (II).




12. Measure voltage between VSA modulator-control unit 47P connector terminal No.16 and body ground.

Is there battery voltage?

YES - Go to step 13.

NO - Check the No.3 VSA MTR (30 A) fuse in the under-hood auxiliary fuse box. If the fuse is OK, repair open in the wire between the No.3 VSA MTR (30 A) fuse and the VSA modulator-control unit, then go to step 14.




13. Check for continuity between VSA modulator-control unit 47P connector terminal No.32 and body ground.

Is there continuity?

YES - Substitute a known-good VSA modulator-control unit, then go to step 16 and recheck. If DTC U0122 is not indicated, replace the original VSA modulator-control unit, then go to step 16.

NO - Repair open in the wire between the VSA modulator-control unit and G302, then go to step 14.

14. Turn the ignition switch OFF.
15. Reconnect all connectors.
16. Turn the ignition switch ON (II).
17. Clear the DTC with the HDS.
18. Do the PCM idle learn procedure.
19. Check for Temporary DTCs or DTCs with the HDS.

Is DTC U0122 indicated?

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