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A/T System




DTC Troubleshooting: U0029 (107-12)

DTC U0029:

F-CAN Communication Circuit Error (F-CAN Bus OFF)

NOTE:

- Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the General Troubleshooting Information How to Troubleshoot the A/T System.
- This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

2. Clear the DTC with the HDS.

3. Check for Pending or Confirmed DTCs in the PGM-FI SYSTEM with the HDS.

Is DTC U0029 indicated in the PGM-F I SYSTEM?

YES -

Go to the DTC U0029 troubleshooting in the PGM-FI SYSTEM PGM-FI System.

NO -

Go to step 4.

4. Check for Pending or Confirmed DTCs in the A/T SYSTEM with the HDS.

Is DTC U0029 indicated in the A/T SYSTEM?

YES -

Go to step 5.

NO -

Intermittent failure, the system is OK at this time. If any other Pending or Confirmed DTCs or DTCs were indicated, go to the indicated DTC's troubleshooting.

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

6. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and wait for at least 2 minutes.

7. Check for Pending or Confirmed DTCs in the A/T SYSTEM with the HDS.

Is DTC U0029 indicated in the A/T SYSTEM?

YES -

Check for poor connections or loose terminals at the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 2. If the PCM was substituted, go to step 6.

NO -

Go to step 8.

8. Monitor the OBD STATUS for U0029 in the DTCs MENU with the HDS.

Does the HDS indicate PASSED?

YES -

If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM Service and Repair. If any other Pending or Confirmed DTCs or DTCs were indicated in step 7, go to the indicated DTC's troubleshooting.

NO -

If the HDS indicates FAILED, check for poor connections or loose terminals at the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 6. If the PCM was substituted, go to step 6. If the HDS indicates NOT COMPLETED, go to step 2.