FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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How to Check ECU's




HOW TO CHECK ECUS

1. Use the scan tool MB991958 (M.U.T.-III Sub Assembly) and the SWS monitor kit to check ECUs.
2. The following ECUs can be checked by using the scan tool MB991958 (M.U.T.-III Sub Assembly) and the SWS monitor kit.
NOTE:
The "ECU COMM Check" function checks the communication status of ECUs. "NG" does not always mean ECU malfunction. If a malfunction is found by the "ECU COMM Check", proceed to "Symptom Procedure" (Refer to Symptom Chart).

SWS monitor kit-compatible ECUs and their conditions





NOTE:

- *1: If the ignition switch is turned to "LOCK" (OFF) or "ACC" when "NG" is displayed beside "ETACS ECU" or the signal request line is abnormal, the scan tool shows "NG" beside the "COLUMN ECU".
- *2: When "NG" is displayed beside "ETACS ECU", the scan tool shows "NG" beside the "FRONT ECU" and "SUNROOF ECU".