What kind of car is it? I'm in power window purgatory with my '73 108 bodied car. I have tested the electric motors by (1) removing door panel, (2) unhooking the motor from the terminal block and (3) CAREFULLY using a battery charger to move the window up and down. All 4 of my motors work fine; The window channel is ancient, but they do go up and down fine. I am in the process of replacing the window channel (NOW THAT'S A PAIN), but I know I have a switch problem.

I took the switches apart (pretty destructive, not recommended) by prying the top of the switch off of the "ears" that keep it on. What I found is the plastic part that keeps spring tension on the contacts has melted. The motors must be laboring and causing too much current to draw. I don't believe my car has window relays. I think they were added to later cars. I am considerinig adding relays at the fuse block in the engine bay to protect my new switches (which I ordered from mercedesshop.com and got today--yeeah).

I could still have a wiring/contact/grounding problem somewhere.

My advice is to try to activate the window with an external source to eliminate the motor and guide.

Sholin

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What else, '73 MB 280 SEL (Lt Blue)
Daily driver: '84 190D 2.2 5 spd.