Code No. U0101: T/M CAN Timeout

  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
  • Whenever the ECU is replaced, ensure that the CAN bus lines are normal.


ACC/FCM-ECU communicates with the CVT-ECU, A/T-ECU via the CAN bus lines.


This diagnosis code is set when the abnormality below is detected:



STEP 1. M.U.T.-III CAN bus diagnostics.

Use M.U.T.-III to perform the CAN bus diagnosis.

Q. Is the check result normal?

Go to Step 2.
Repair the CAN bus lines (Refer to GROUP 54C - Troubleshooting ).

STEP 2. M.U.T.-III other system diagnosis code.

Check the CVT diagnosis code (Refer to GROUP 23A -Troubleshooting ) or the automatic transmission (FF) diagnosis code (Refer to GROUP 23C -Troubleshooting ).

Q. Is the diagnosis code set?

Perform the relevant troubleshooting.
Go to Step 3.

STEP 3. M.U.T.-III other system diagnosis code.

Check if the diagnosis code No. U0101 is set to other ECU.

Q. Is the diagnosis code set?

Replace the CVT-ECU (Refer to GROUP 23A - CVT-ECU ) or the A/T-ECU (Refer to GROUP 23C - A/T-ECU ).
Go to Step 4.

STEP 4. Check whether the diagnosis code is reset.

Q. Is diagnosis code No.U0101 set?

Replace the ACC/FCM-ECU (Refer to ).
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).