Disconnect the plug at the switch for the rear and and see if the fuse still blows. Repeat with the front.

I would think that the problem would not be in the rubber tube that takes the wires through the space between the chassis and the door. Those wires are all hot, I think, with the return going through chassis ground. 'I would first look for a frayed wire somewhere between the switch on the console and the door. Try FI's test to see if you can further isolate the problem.

__________________

"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

Ok, finally got out to work on the car today....

I disconnected the switch from the rear door and tried rolling down the window with the front switch and the fuse did not blow. Then I disconnected the front switch and tried rolling down the window with the rear switch and it still did not blow. In neither case did the window roll up or down though, as the window only rolls up and down if both switches are plugged in. The fuse also only blows if both switches are plugged in. And it seemed that the fuse only blew if the front switch was used.

So where should I look now? The wires going from the front switch to the rear switch?

Thanks,
David

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1985 300D. 179,000 miles.

You will most likely have a broken wire in the door post on the passenger side. I had same problem and had a broken wire in door post to passenger rear where the front seat belt mounts. I went thru a lot of fuses til I figured that one out! Easy to do just a bit time consuming when you are doing it the first time. Good Luck!

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1987 300 DT

I had the same problem on the SD. Took almost one year to finally solve it.

Indlulge me.

Remove the switch from the RR door and install it in the LR door.

Try to blow the fuse.

Report back.

Well well well, it was the brand new switch I ordered from ******** AZ all along!!!

I took it out, put in the other one, and bam, working again, no fuses blowing, nothing. Well, I'm happy it's not a wire!!! That would have been much more annoying to fix.

Could it be because this switch is not an original Mercedes one... Just looked at the box, made in china.

Or could it be that it's my least powerful window and it couldn't handle a new switch??

David

__________________
1985 300D. 179,000 miles.

Cheap is not good.
Good is not cheap.
Caveat emptor.

__________________

"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

Cheap can sometimes be good, most of the parts I've ordered from ******** AZ have been genuine Mercedes made in germany parts and the prices are pretty damn cheap.

I'll for sure be making sure everything I order from there is from Germany if possible, no China crap. I'm not into buying products from China anyways.

David

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1985 300D. 179,000 miles.

Yes, that's what I figured.

It's got something to do with the change in design of the switch. I suffered through the exact same problem with a brand new switch from Performance Products. They were totally useless in helping me with the problem........just took the switch back and gave me credit.

I located a used switch........in very nice condition.........and it solved the problem.

I'm very glad to see that someone else has suffered this issue..........apparently, it's generic.

I did contact Mercedes Benz about this problem and, naturally, they stated that their OE switch would not have such an issue.

Who knows?

I'm glad to hear that you got it resolved. On my 87 wagon, I tried the switches and thought I had it licked, then POP i blew another fuse out of the blue. It turned out that the wires in the door jamb were failing. and the kids using the back doors caused it to be intermittent. Ended up splicing in new supple wire in the hinge area to facillitate movement. Hope your fix sticks.

__________________
Dean