Shift Lever, (TC-SST)

DTC U0121: ASC Time-out Error

CAUTION
^ If there is any problem in the CAN bus lines, an incorrect diagnostic trouble 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.

JUDGMENT CRITERIA
The periodic communication data from the ASC-ECU cannot be received.

PROBABLE CAUSES
^ The CAN bus line is defective.
^ Malfunction of ASC-ECU
^ Malfunction of the shift lever-ECU

DIAGNOSTIC PROCEDURE

STEP 1. Scan tool CAN bus diagnostics
Using the scan tool, diagnose the CAN bus lines.
Q: Is the check result normal?
YES: Go to Step 2.
NO: Repair the CAN bus lines. After repairing the CAN bus line, go to Step 2.

STEP 2. Scan tool diagnostic trouble code
Check the ASC diagnostic trouble code. Diagnostic Trouble Code Descriptions
Q: Is the DTC set?
YES: Perform the relevant troubleshooting.
NO: Go to Step 3.

STEP 3. Check whether the DTC is reset.
Q: Is DTC No. U0121 set?
YES: Replace the shift lever assembly.
NO: Intermittent malfunction.