ECM-EPS Control Unit

DTC Troubleshooting: U0131

DTC U0131: F-CAN Malfunction (ECM-EPS Control Unit)

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information. Reading and Clearing Diagnostic Trouble Codes

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

2. Check for Pending or Confirmed DTCs with the HDS.

Are DTC U0028 and U0131 indicated at the same time?
YES - Go to troubleshooting for DTC U0028. U0028

NO - Go to step 3.


3. Clear the DTC with the HDS.

4. Check for Pending or Confirmed DTCs with the HDS.

Is DTC U0131 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 EPS control unit and the ECM.


5. Check for communication between the HDS and the EPS system.

Does the HDS communicate with the EPS control unit?
YES - Go to step 6.

NO - Go to the EPS system symptom troubleshooting for EPS indicator does not go off, and no DTCs are stored. EPS Indicator Does Not Go Off, and No DTCs Are Stored (With EPS)


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

7. Jump the SCS line with the HDS.

8. Disconnect EPS control unit connector D (28P).

9. Disconnect ECM connector A (44P).

10. Check for continuity between ECM/PCM connector terminal A36 and EPS control unit connector D (28P) terminal No. 1.

Is there continuity?
YES - Go to step 11.

NO - Repair open in the wire between the ECM/PCM (A36) and the EPS control unit, then go to step 12.






11. Check for continuity between ECM/PCM connector terminal A37 and EPS control unit connector D (28P) terminal No. 15.

Is there continuity?
YES - Substitute a known-good EPS control unit, Service and Repair then go to step 12 and recheck. If DTC U0131 is not indicated after substitution, replace the original EPS control unit, Service and Repair then go to step 12.

NO - Repair open in the wire between the ECM/PCM (A37) and the EPS control unit, then go to step 12.






12. Reconnect all connectors.

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

14. Reset the ECM with the HDS.

15. Do the ECM idle learn procedure. ECM/PCM Idle Learn Procedure

16. Check for Pending or Confirmed DTCs with the HDS.

Is DTC U0131 indicated?
YES - Check for poor connections or loose terminals at the gauge control module, the EPS control unit, and the ECM, then go to step 1.

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