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. Refer to DIAGNOSIS .
- STEP 2. M.U.T.-III data list
Item 50: Brake switch
OK: The service data changes in response to the brake operation.
Q: Is the check result normal?
YES : Intermittent malfunction
NO : Go to Step 3.
- STEP 3. Check the following connector:
- C-304 ETACS-ECU connector
- C-312 ETACS-ECU connector
- C-124 Stoplight switch connector
Check the contact status of the terminals.
Q: Is the check result normal?
YES : Go to Step 4.
NO : Repair the defective connector.
- STEP 4. Stoplight Switch Check
Refer to BRAKE PEDAL .
Q: Is the check result normal?
YES : Go to Step 5.
NO : Replace the stoplight switch.
- STEP 5. Check for open circuit in the wiring harness between the stoplight switch connector and the ETACS-ECU connector.
Between C-124 Stoplight switch connector (terminal No. 2) and C-304 ETACS-ECU harness-side connector (terminal No. 1)
Q: Is the check result normal?
YES : Go to Step 6.
NO : Repair the wiring harness.
- STEP 6. Check for open circuit or short to ground in wiring harness between the ETACS-ECU connector and the intermediate connector
Between C-312 ETACS-ECU harness-side connector (terminal No. 16) and C-129 intermediate (terminal No. 9)
Q: Is the check result normal?
YES : Go to Step 7.
NO : Repair the wiring harness.
- STEP 7. Check for open circuit in wiring harness between the stoplight switch connector and the intermediate connector
Between C-124 stoplight switch connector (terminal No. 1) and C-129 intermediate (terminal No. 9)
Q: Is the check result normal?
YES : Go to Step 8.
NO : Repair the wiring harness.
- STEP 8. Symptom recheck after erasing diagnosis code
Q: Is the check result normal?
YES : Intermittent malfunction
NO : Replace the ETACS-ECU, and then go to Step 9.
- STEP 9. Symptom recheck after erasing diagnosis code
Q: Is the check result normal?
YES : Intermittent malfunction
NO : Replace TCM.