Rear headrest wouldn't release
 

Hello everyone,

Could anyone show me how to manually release the rear headrests of my 94 C280. They are stucked to the up position. I think the vacuum leak may have caused the pushbutton switch to be inactive.

Because of the vacuum leaking problem, the air has been blowing up to the windshield lately instead of to the center vents. Can the control diaphram be permernently latch up so it won't change to the defrost position?

By the way, how do I check where the leak is at? I opened the cover below my golve box, and couldn't see any visible sight of problem.

Your assistant will be greatly appreciated.

I'm not familiar with C280. But on my 91 300D the electrical switch is loacted under the rear seat of driver side next to the window control unit. you can disconnect those blue/white vacuum hoses and suck on them/use a vacuum pump to release the headrests. The other way around is to realease them from the trunk area. take the panel behind the seat off, you'll see where the vacuum lines connect to, disconnect them and use a spare vacuum tube to release them. you might be able to push the locking rod back from there...not sure!

Vacuum leak is not visible to human eyes! You can spray something on it and watch it disappears...not a good way. you'll need a vacuum tester and a vac pump as well.

W202 rear headrest release is partly electrical and partial vacuum operated.
The switch on the dash is electrical, under the rear deck is an electric operating vacuum valve that has to click (sound is faintly hearable) after which it will allow vacuum to release the headrests.
If there is a small vacuum leak, you should be able to release the headrestst by pushing the switch a little longer...if this does not help, you need to check whether you have an electrical or vacuum problem...You can get to the control valve after removing the first aid kit with compartment box. From the valve 2 vacuum lines will go to the headrest release solenoids and 1 vacuum line to the front of the car...it is connected at the vacuum clustering connector under the black plastic cover at the right side under the hood (white vacuum line with or without a colored stripe).

greetingz,