W140 Blower Motor

bullet

Air Recirculation Filter R&R; Maintenance Job # 8383

The cabin filter is a routine replacement item.  The service interval recommended by Mercedes-Benz is 45K miles/2 years.

The job is basic, though there are a few items that need to be observed in the process.

Part # 140 835 00 47 lists for $42.50

bullet

Blower regulator R&R

Complaint:  Blower fan does not change speeds.  Operates only at slow speed.

Solution:  The dealer diagnosed the blower motor as bad, but when I double-checked with my service writer he suggested I replace the blower regulator.  Works great.  

Part # 140 821 83 51 lists for $338.00

 

Note:  These images may not represent every detail of the process.  

blowermotor01.jpg (43457 bytes)

Lift the weather strip (yellow arrow) and turn the Duz fasteners 1/4 CCW (white arrows)

blowermotor02.jpg (84862 bytes)

Lift the cover off over the right wheelhouse

blowermotor03.jpg (90864 bytes)

Remove screws for small cover

blowermotor04.jpg (79500 bytes)

Lift off cover and lift out screen

blowermotor05.jpg (37029 bytes)

Close up of screen

blowermotor06.jpg (109508 bytes)

Lift remainder of weather strip from air duct.

Remove many screws holding air duct cover (green arrows)

blowermotor07.jpg (99218 bytes)

Air duct cover removed

blowermotor08.jpg (97825 bytes)

Disconnect sensors from left end of air duct.  Large sensor twists CCW slightly to remove

blowermotor09.jpg (97863 bytes)

Image shows mounting holes of sensors in left end of air duct

blowermotor10.jpg (101439 bytes)

Air duct removed

blowermotor11.jpg (108303 bytes)

Cabin filter

 

blowermotor12.jpg (115563 bytes)

Lift cabin filter

blowermotor13.jpg (128396 bytes)

Blower regulator mounting details

blowermotor14.jpg (110440 bytes)

Remove mounting screws

Pry connector mounting clip off boss on housing

Disconnect

To replace, just reverse the procedure.

Be sure to clean the mounting surface for the blower regulator heat sink and use special grease.

Torque regulator mounting screws per spec

         
         
 

Hit Counter since 1/11/03