Control System

DTC Troubleshooting: U0029

DTC U0029:

F-CAN Communication Line Error

NOTE:

- Make sure the HDS communicates with the PCM and other vehicle systems. If it does not, go to DLC Circuit Troubleshooting Testing and Inspection.
- If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.

1. Clear the DTCs with the HDS.

2. Turn the ignition switch to LOCK (0) and then back to ON (II).

3. Wait for at least 6 seconds.

4. Check for DTCs with the HDS.

Is DTCs U0029 indicated?

YES -

Go to step 5.

NO -

Intermittent failure, the system is OK at this time. Check for loose or poor connections, or worn/shorted wires. If the connections are good, check for the battery condition Testing and Inspection and the charging system.�

5. Check for DTCs in the PCM with the HDS.

Are any DTCs indicated?

YES -

Go to the indicated PCM DTC's troubleshooting.�

NO -

Go to step 6.

6. Do the gauge control module input test.

Are all inputs OK?

YES -

Go to step 7.

NO -

Repair the faulty input, then recheck the DTCs.�

7. Substitute a known-good gauge control module.

8. Clear the DTCs with the HDS.

9. Turn the ignition switch to LOCK (0) and then back to ON (II).

10. Start and run the engine for at least 5 seconds, then turn the engine off.

11. Check for DTCs with the HDS.

Is DTC U0029 indicated?

YES -

Go to step 12.

NO -

The original gauge control module is faulty; replace it.�

12. Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM.

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

Is DTC U0029 indicated?

YES -

Check for poor connections or loose terminals at the gauge control module and the PCM. If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1.

NO -

If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM Service and Repair.�