DTC Troubleshooting
DTC U0073: F-CAN Malfunction (BUS-OFF)DTC U0155: F-CAN Malfunction (PCM-Gauge Control Module)
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.
1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS.
Is DTC U0073 and/or U0155 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, the navigation unit, the engine mount control unit, the VTM-4 control unit, the TPMS control unit, and the PCM.
4. Turn the ignition switch OFF.
5. Jump the SCS line with the HDS.
6. Disconnect PCM connector A (44P).
7. Remove the gauge control module.
8. Disconnect the gauge control module connector A (20P).
9. Disconnect navigation unit connector A (20P) (if equipped).
10. Disconnect the engine mount control unit 20P connector (if equipped).
11. Disconnect the TPMS control unit connector B (20P).
12. Disconnect the VTM-4 control unit connector A (22P) (if equipped).
13. Disconnect the VSA modulator-control unit 47P connector.
14. Check for continuity between PCM connector terminals A1 and A36 and body ground individually.
Is there continuity?
YES - Repair short in the wire between the gauge control module, the VSA modulator-control unit, the navigation unit, the engine mount control unit, the VTM-4 control unit, the TPMS control unit, the engine mount control unit, and the PCM (A36 (AD), then go to step 19.
NO - Go to step 15.
15. Check for continuity between PCM connector terminals A1 and A36.
Is there continuity?
YES - Repair short in the wire between PCM connector terminals A1 (CANL line) and A36 (CANH line), then go to step 19.
NO - Go to step 16.
16. Check for continuity between PCM connector terminal A36 and these connector terminals:
Is there continuity between the PCM terminal and each of the terminals in the chart?
YES - Go to step 17.
NO - Repair open in the wire between the PCM (A36) and the appropriate connector, then go to step 19.
17. Check for continuity between PCM connector terminal A1 and these connector terminals:
Is there continuity between the PCM terminal and each of the terminals in the chart?
YES - Go to step 18.
NO - Repair open in the wire between the PCM (A1) and the appropriate connector, then go to step 19.
18. Referring to the chart below, select the row that most closely represents the combination of DTCs retrieved from the PGM-FI, VSA, VTM-4, and TPMS systems. Then check the connections at the control module indicated in the last column. If all the connections are OK, substitute the control module.
After substituting the control module, check for DTCs with the HDS.
Are the DTCs still indicated?
YES - Substitute the remaining control modules, one at time, until the DTCs are no longer present, then replace the control module that made the DTCs go away. After replacing the faulty control module, go to step 19.
NO - Replace the faulty control module, then go to step 19.
19. Reconnect all connectors.
20. Turn the ignition switch ON (II).
21. Reset the PCM with the HDS.
22. Do the PCM idle learn procedure.
23. Check for Temporary DTCs or DTCs with the HDS.
If DTC U0073 and/or U0155 indicated?
YES - Check for poor connections or loose terminals at the gauge control module, the VSA modulator-control unit, the VTM-4 control unit, the TPMS control unit, 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.