There have been many mentions of broken wires in power window threads here and elsewhere, especially involving W124 cars. The wiring that goes through the B pillar to the rear doors seems especially liable to fail. I thought you might like to see an example.

I had noticed for some time that the right rear window in my 1987 300D would not work occasionally. Then it changed to blowing the fuse (it's the "G" fuse in that car). Since the same fuse powers the driver's window, it was definitely worth fixing.

After removing the door skin and the B pillar trim panel, I removed the plastic plug body from the power window cable and pulled the cable out through the rubber pass-through. As soon as the cable came into view I could see the problem (first picture). I had expected the wires to have broken inside the cable and touched each other; what I saw was that the wires had broken through the cable, allowing the raw ends to touch the body of the car, causing the fuse to blow when the window was operated. It looked like the cable had been tied in a knot! (In defense of Mercedes, this might have happened when the PO installed his aftermarket alarm system.)

With the cable sheath cut away, the damaged wires -- two were actually broken -- could be seen. The overall effect was much worse than I had expected. No wonder it blew fuses!

After repairing the breaks and properly insulating the wires, I put everything back together. The window now operates correctly and the fuse doesn't blow. Makes you wonder what the cables in the other three doors look like!

Jeremy

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__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970