MMCS
TSB Revision
CHASSIS ELECTRICAL
54A-469
STEP 1. Using scan tool MB991958, diagnose the CAN bus
line.
CAUTION
To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958. Refer to "How to connect the
Scan Tool (M.U.T.-III)
P.54A-458
."
(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.
Q: Is the CAN bus line found to be normal?
YES : Go to Step 2.
NO : Repair the CAN bus line (Refer to GROUP 54C,
Diagnosis
P.54C-17
).
STEP 2. Using scan tool MB991958, read the ETACS-ECU
diagnostic trouble code.
Check again if the DTC is set to the ETACS-ECU.
Q: Is the DTC set?
YES : Diagnose the ETACS-ECU (Refer to
P.54A-732
).
NO : Go to Step 3.
STEP 3. Using scan tool MB991958, read the A/C
diagnostic trouble code.
Check if DTC U0141 is set to the A/C-ECU.
Q: Is the DTC set?
YES : Go to Step 4.
NO : Go to Step 5.
AC608435
Data link connector
MB991827
MB991824
MB991910
AB