Code No.U0101: Transmission CAN timeout


caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be stored. Prior to this diagnosis, diagnose the CAN bus lines.
  • Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
  • When the ETACS-ECU of vehicles without KOS is replaced, the encrypted code of the ignition key needs to be registered to the ETACS-ECU. (If the encrypted code is not registered, the engine cannot be started. Register the encrypted code as described in GROUP 54A, Immobilizer System - How to Register Key ID .)

OPERATION


4WD-ECU communicates with engine-ECU and CVT-ECU or A/T-ECU via the CAN bus lines.

DIAGNOSIS CODE SET CONDITION


The system cannot receive any data from the engine-ECU and CVT-ECU or the A/T-ECU for certain period.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

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 stored?
Perform the relevant troubleshooting.
Go to Step 3

STEP 3. ETACS-ECU coding data check.
Check the transmission coding data stored in ETACS-ECU for any abnormality (Refer to GROUP 00 - Coding Reference Table ).

Q. Is the check result normal?
Go to Step 4
Replace the ETACS-ECU. (Refer to GROUP 54A - ETACS .) Then go to Step 5.

STEP 4. Check whether the diagnosis code is stored again.

Q. Is diagnosis code No.U0101 stored?
Replace the 4WD-ECU (Refer to ). Then go to Step 5 .
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

STEP 5. Check whether the diagnosis code is stored again.

Q. Is diagnosis code No.U0101 stored?
Return to Step 1.
This diagnosis is complete.