Continuously Variable Transaxle (CVT)

DTC U0121: CAN Time-out Error (ABS)

DIAGNOSTIC FUNCTION
TCM determines that malfunction is present if the periodic communication data sent from the ABS-ECU via CAN bus lines is abnormal.

JUDGEMENT CRITERIA
TCM cannot receive the periodic communication data from ABS-ECU.

PROBABLE CAUSES
^ Malfunction of the CAN bus
^ ABS-ECU malfunction
^ Malfunction of TCM

DIAGNOSTIC 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?
YES: Go to Step 2.
NO: Repair the CAN bus lines.

STEP 2. M.U.T.-III diagnosis code
Check if the ABS-related diagnosis code is set.

Q: Is the ABS-related diagnosis code set?
YES: Carry out the appropriate troubleshooting.
NO: Go to Step 3.

STEP 3. Symptom recheck after erasing diagnosis code

Q: Is the check result normal?
YES: Intermittent malfunction
NO: Replace TCM.