How To Check Ecus

Use the scan tool MB991958 (M.U.T.-III Sub Assembly) and the SWS monitor kit to check ECUs.
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

ECU CHECK CHART

ITEM No.	ECUS TO BE CHECKED	DISPLAY ON SCAN TOOL	NORMAL CONDITION	ECU CONDITION
80	Column switch (column-ECU)	COLUMN ECU	OK*¹	All of the column switch, power supply, ground and interconnecting communication lines are normal
83	ETACS-ECU	ETACS-ECU	OK	All of the ETACS-ECU switch, power supply, ground and interconnecting communication lines are normal
84	Front-ECU	FRONT ECU	OK*²	All of the front-ECU, power supply, ground and interconnecting communication lines are normal
86	Sunroof motor assembly (sunroof-ECU)	SUNROOF ECU	OK*²	All of the sunroof motor assembly, power supply, ground and interconnecting communication lines are normal
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".