C 240 4MATIC Wagon (203.281) V6-2.6L (112.916) (2003)
Air Door Actuator / Motor: Customer Interest
A/C - Ticking/Whistling Noises From Dash Area
Date: October 30, 2008
Order No.: P-B-83.00/78b
Supersedes: P-B-83.00/78a dated Jan. 30, 2007
Group: 83
Revision History
SUBJECT:
Model 203.040/061/064/065/081/084/261/264/281/284/740/747/764 Up to Model Year 2004
Instructions for Stepper Motor Replacement
If you receive customer reports in the above model vehicles of a ticking noise coming from the area of the instrument panel, incorrect air distribution or
whistling sounds from the vents, the cause could be malfunctioning stepper motors or damaged lever arms. Please perform the below instructions for
replacing the following stepper motors and lever arms.
C-ACC, option code 581
M2/10 Left footwell flap stepper motor or lever arm
M2/19 Left fresh air flap stepper motor
M2/20 Right fresh air flap stepper motor
ACC, option code 580
M2/15 Left and right footwell flap stepper motor and lever arm
M2/21 Fresh air flap stepper motor
Diagnostic: Use SDS to confirm specific stepper motor malfunctions using the instructions below. Control units -> Air conditioning -> C-AAC, ACC ->
Control unit adaptations -> Check adjustment range of positioning motors.
Any motors out of range will be shown operating in the red zone of the graphic display. There must be an out of range condition for the graphic display
to appear.
If there is a ticking noise coming from the area of the instrument panel, it could be a damaged lever arm and it is not necessary to replace the footwell
stepper motor. The cause of the noise may be the hex shaped drive shaft of the motor turning in a fractured lever. New updated levers are available
separately in kit A203 830 00 33.
Procedure:
1. Remove the radio, refer to WIS document AR82.60-P-7502P.
2. Disassemble the center console enough to slide it back to disengage it from the bottom of the center dash, refer to WIS document
AR68.20-P-2000P.