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

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

 

Lift the weather strip (yellow arrow) and turn the Duz fasteners 1/4 CCW (white arrows)	Lift the cover off over the right wheelhouse	Remove screws for small cover	Lift off cover and lift out screen	Close up of screen
Lift remainder of weather strip from air duct. Remove many screws holding air duct cover (green arrows)	Air duct cover removed	Disconnect sensors from left end of air duct.  Large sensor twists CCW slightly to remove	Image shows mounting holes of sensors in left end of air duct	Air duct removed
Cabin filter	Lift cabin filter	Blower regulator mounting details	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