STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
(1) caution | To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. |
Connect scan tool MB991958. Refer to "How to connect the scan tool (M.U.T.-III)
."
(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Is the CAN bus line found to be normal?
Go to Step 2. Repair the CAN bus line (Refer to GROUP 54C, Diagnosis ).
STEP 2. Using scan tool MB991958, check for any diagnostic trouble code.
Check if DTC is set in the KOS-ECU <vehicles with KOS> or WCM <vehicles with WCM>.(1) Turn the ignition switch to the "ON" position.
(2) Check whether the KOS or WCM related DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Is the DTC set?
<vehicles with KOS> :
Troubleshoot the KOS (Refer to GROUP 42B, KOS ). <vehicles with WCM> :
Troubleshoot the WCM (Refer to GROUP 42C, WCM ).Go to Step 3.
STEP 3. Check the keyless operation key <KOS> or keyless entry transmitter <WCM>.
STEP 4. Using scan tool MB991958, check data list.
STEP 5. Check hazard indicator assembly connector C-246 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
STEP 6. Check the theft-alarm indicator.
STEP 7. Check ETACS-ECU connector C-406 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
STEP 8. Measure the voltage at ETACS-ECU connector C-406.
STEP 9. Check the Wiring harness between ETACS-ECU connector C-406 (terminal No. 2) and fusible link (36).
STEP 10. Check ETACS-ECU connector C-417 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
STEP 11. Check the Wiring harness between ETACS-ECU connector C-417 (terminal No. 2,9) and hazard indicator assembly connector C-246 (terminal No. 13,12).
STEP 12. Retest the system.