Code No.U0121: ASC Time-out Error


caution
  • 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.

OPERATION



DIAGNOSIS CODE SET CONDITIONS



PROBABLE CAUSES



  • The CAN bus line is defective.
  • Malfunction of ASC-ECU
  • Malfunction of AWC-ECU

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 diagnosis code.
Check the ASC diagnosis code. (Refer to GROUP 35C - Troubleshooting ).

Q. Is the diagnosis code set?
Perform the relevant troubleshooting.
Go to Step 3.

STEP 3. Check whether the diagnosis code is reset.

Q. Is diagnosis code No.U0121 set?
Replace the AWC-ECU. (Refer to ). Then go to Step 4.
Intermittent malfunction. (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

STEP 4. Check whether the diagnosis code is reset.

Q. Is diagnosis code No.U0121 set?
Return to Step 1.
This diagnosis is complete.