W124 e220 cabriolet electric window

[Deleted member 11979]

Just a quite note that maybe of use to people in the future, my drivers side electric window went down, then would not come back up again , particularly disappointing!

After arming myself with advice from previous posts here I st about diagnosing the problem.

First port of call the fuse box, sadly all in order there.


Next I checked the switch, as suspected it was ok (the roof switch wouldn't raise the window either, so I thought the switch was ok.

Things would have to get more in depth, so I inspected the wires between body and door for chaffing, all sound there.

Next off came the door panel, swapped the wires on the motor, pressed down, and the window went up!

Hmmmmmmm

Put the terminals back the way they should be, pressed down, and dow nwent the window, pressed up, and down stayed the window.

Put a meter on the motor terminals and pressed up, both were live!

Hmmmmmmm

Well and truly stumped I could hear a small click from the back of the car when I pressed the up button.

Took the seat out, saw a black box with wires everywhere. Merceds was printed on the top, it looked expensive. Very expensive.

Decided to hit it.

Pressed the switch.

Window went up!

Home for tea and medals.

Another day wasted.

Moral of this story, check the black box before disassembling the rest of the car.

Hope it's of use to someone.

 

[Smiley]

Is this the window relay? is it underneath the rear seat? Sounds strange that it should be OK on the way down but not up. But a useful tip.

 

[Deleted member 11979]

It is under the rear seat, so I guess thats what it is, a large rectangular black box with several wires in and out. On the passenger side.

 

[jttc]

Thanks CCAALLVVIINN for advising to give the black box under the rear seat a few hits.

Problem with my driver side electric window was solved.

Problem was that the window will not go down. So when my mechanic opened up the door clapping to check, he found that the motor is still running and in the up direction. When he swap the wires around, then the window can only go down with the motor keep on running.

Told him to give the black box a few gentle "hits" and true enough, the problem was solved.

 

[rumelk]

. Merceds was printed on the top, it looked expensive. Very expensive.

Decided to hit it.

ROTFL, i actually fell off my seat from laughter, sounds like something i would do LOL