MANUAL A/C DIAGNOSIS
TSB Revision
HEATER, AIR CONDITIONING AND VENTILATION
55A-100
STEP 1. Using scan tool MB991958, diagnose the CAN bus
line.
CAUTION
To prevent damage to scan tool (MUT-III), always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool (MUT-III).
(1) Connect scan tool MB991958 to the data link connector.
(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 lines (Refer to GROUP 54C,
precautions on how to repair the can bus lines
P.54C-5
).
STEP 2. Using scan tool MB991958 read the powertrain
control module diagnostic trouble code.
Check whether an engine and automatic transmission DTCs
are set or not.
(1) Turn the ignition switch to the "ON" position.
(2) Check for engine and automatic transmission DTCs.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES : Diagnose the powertrain control module (Refer to
GROUP 13A, Diagnostic Trouble Code
P.13A-33
<2.4L> or GROUP 13B, Diagnostic Trouble Code
P.13B-34
<3.8L>).
NO : Go to Step 3.
AC305412
AB
MB991910
DATA LINK
CONNECTOR
MB991824
MB991827
AC305412
AB
MB991910
DATA LINK
CONNECTOR
MB991824
MB991827