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1983 300D
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Discussion Starter · #1 · (Edited)
I rolled my rear driver side window down a couple inches last week and it won't roll back up.

Is there a quick way to get the window back up without taking the door apart? I've tried pushing it back up but it won't budge, or I'm not strong enough.

It's not making any noises when I press the switch, so I suspect it's some kind of electrical problem rather than mechanical. I have ruled out a fuse because all the other windows work from the front console. However, neither of the rear door window switches work, so I'm thinking there might be a problem with the switch-lockout-switch combo on the left of the console. Maybe the two rear door switches are permanently locked out and the "up" for the rear window console control is shorted out? My next step is to take that thing apart and clean the switches.

But, I need my window up in the mean time!
 

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1985 300D Turbo-diesel
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you can remove the switch from the door find the two wires that run to the motor(I can't remember the colors off the top of my head) then using a 12 volt power source you can roll the window up or down-NOTE- this is assuming the motor itself did not fry

on your center console-have you replaced the switch set with new switches? seems like a large amount of the new sets seem to have malfunctioning safety switches and don't light up either

now the hardest part of the electrical rear windows is the opening and closing of the doors...it actually causes the wires to part and seperate, so while you may get continuity, they may be touching causing a short, which means no power, I had to fix my wire set-using short pieces of new wire and soldering them in(varying lengths so all the solder points weren't in the door hinge, or aligned with one another, it took over two hours, as you have to remove the B pillar cover, and try to get the wires through the loom and the door, fortunately for me the drivers rear was always used the most and so was the only one with the problems(have had to replace the door check twice on the rear and once on the front)
 

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1983 300D
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Discussion Starter · #3 ·
Thanks for the suggestions. The switches are all original right now. I ordered a replacement set for the left console side (switch-lockout-switch) because the existing ones are all worn out, but it won't arrive until next week.

Assuming somehow muscling the window up is out of the question, it looks like I'll be taking apart switches trying to clean them or figure out if there's a short somewhere.
 

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1985 300D Turbo-diesel
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I think you'll end up finding the wires that come from the B-pillar to the rear doors have broken, this is the most common cause for rear doors not working, minus the testing of the safety switch in the center console, the reason for the wires breaking happens to be how they are fastened in the B-pillar; they are clamped closest to the rear of the pillar, then make a sharp 90 degree turn to go into the door-poor design, it puts too much stress on the wires and they break, you don't have this problem with the front as the wires come in much straighter

testing the safety switch is easy all it does is allow continuity to go to the rear doors, so with a multi-meter you can depress and release the button, if you get continuity from the two center, brown wires(safety off), and then no continuity(safety on) then your safety switch works
 

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1983 300D
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Discussion Starter · #6 ·
OK, I've determined it was a bad switch.

I used the Mercedessource video on removing the center console to get to the switches:



This is the underside of the console with all the switches unhooked. I noted that the plastic pin you see at the bottom of the image is intact--the guy in the video said many of them are broken from people trying to remove the console the wrong way:



I reversed the wiring to the switches so the front driver's side switch was connected to the rear window and vice versa. One thing I noticed is that the switches will not operate unless ALL the harnesses are plugged in. Bam, the rear window rolled right up when I hit the front driver's switch:



So, the rear switch and possible the lockout are broken. I've got a replacement on the way.
 

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If the wires were broken, though, why would the window roll down? It seems like it wouldn't roll up or down if there was something wrong with the wiring going to the back door.
just enough contact for it, I know sounds weird, but it happened to me, lowered the window halfway, drove into town, couldn't get it to roll up, tried swapping switches(what you did with the drivers center console switch) but couldn't roll it up, went to test for continuity, had it, but very little of it

also is it really necessary to remove the console, couldn't you have just pried on the switch then pulled the connections up with the switch? That's what I do, done in half the time needed to remove the cover plate
 

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1983 300D
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Discussion Starter · #8 ·
also is it really necessary to remove the console, couldn't you have just pried on the switch then pulled the connections up with the switch? That's what I do, done in half the time needed to remove the cover plate
I was just paranoid about chipping the wood. After I got it apart, I noticed how easily those switches come out. In fact, they kept popping out when I was putting it back together.

Thanks for all the input--I really appreciate it. If this hadn't fixed the problem, I was going to try your idea next! :cool:
 
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