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Electric Window Relays?

2501 Views 21 Replies 7 Participants Last post by  MBeige
G
on the CDT, 85, where in gods name is if any the relays for the electric window motors. according to my father, the german meister mechaniker, it should have them in a relay case under the hood. however there is none to be found? are they possibly under the dash cover, or do they simply not have them? my passenger front window has stopped going down suddenly, and the age old trick of switching out the swithes from drivers side that i know work had no effect, thus my switch is in order. i would like to know before tearing up the under covers or removing door panels, so if anyone has an idea, id appreciate it.

JMD

its not the fuses, been checked.

http://www.JMDLubricants.com
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I could be wrong, but I don't think there are relays for the windows. You're positive the switch isn't bad? Check your motors.
G
yup, the passenger side switch assembly rolls the drivers side windows right down, so its definately not the switch. surprisingly none of the service books iv seen online and in my possesion even mention anything at all, as if they want u to have to go to benz and pay top dollar for answers. uv never heard of a fusable link in the doors or anything?

JMD

http://JMDLubricants.com
I haven't heard anything about a fusible link. It really wouldn't make sense, since the circuit is fused in the fuse panel, to put a fusible link between the switch and motor. Of course, I keep my manual right next to my computer and as soon as I read your post I looked it up and much to my avail, just as you have said, I found nothing. It takes all of 3 minutes to pull off the door panel, check your wires for continuity, or try applying 12V directly to the motor. Of course, you want to use a fused jumper lead.
G
cool. will now go outside and pull the door panel, now that i have no other choice. dad says he can get it on good as new, since benz parts are so well made, i just have been reluctant to take it off because my experience with lesser quality vehicles (Hondas, BMW's, VW/Audi etc.) is that once you take the panel off, it never looks or fits like new ever again, and always looks like its been off and messed up etc. oh well, he says itll be like new, just like on a customer's car, so i'll let him do it. also can finally remount my custom cutout speaker mounted in the door, which had fallen off due to a bad job at the sounds shop, so i hear u have to remove the panel really to get a good solid backing anything on there for the srews to hold into. well, off i go, another headache awaits.

JMD
There is one main "ice cube" relay located behind the instrument cluster that supplies power to all of the windows.
G
so in the case of it failing, would all the windows stop, or just one?
If I understand what your saying, your window goes up but not down?? This happened to me in reverse, the drivers door window would go down but not up, when I took off the door panel which is a snap, only thing you have to watch out for is the storage area kind of locks in there and can break if not taken out slowly, that would leave you with a storage compartment thats flaps around, anyway there is a block in there where the wires screw into, if you reverse the wires the window switches will operate in reverse if pressing up doesn't make the window go down then you probably have something wrong with the motor....I had to drive around like that for awhile then all of a sudden the window started working again! And hasn't given me problems since (I did rewire it back to original and it works fine) no idea what it was...gremlins???
G
wierd, simply wierd. i hope it turns out that simple AND THAT CHEAP!!! i havent yet removed my panel today since father's not around, and i want to take NO risks of screwing anything up, so im waiting till he arrives.
Let us know how it turns out champ, way to be intimidated by a door panel lol.
the relays for the windows are under the dash somewhere. i remember a few years ago it was a headache to find them as well!

i dont remember by heart where exactly they are, but they are under the dash!
G
yeah yeah, i want my car to look like perfection, and having never taken one off before, i wont assume it will turn out right. i will not give myself a headache to have to fix, so it will have to be done correctly, and not just according to what some haynes book says.
AMSOIL300CDT - 3/10/2005 11:19 AM

yeah yeah, i want my car to look like perfection,
I know exactly what you mean. When your dad arrives, be ready to dive in! Goodluck! And as others said let us know how it goes.

[:p]
I'd like to revisit this since yesterday all 4 windows on mine ceased to function. No power at the fuse box for the window fuses. I was able to jumper power into that point to close the windows, so I'm sure it's either the relay(s), or power supply to them or the fuse block.

The wiring diagram I'm looking at shows two relays for the windows; one appears to be activated by the rear window lockout switch, and the other is for the front windows (although I havn't yet worked out the details of how they work).

So I'm looking for any more detail (if available) on where the relays are located.

Thanks.
G
what an excellent coincidence. i too have to bring this up again after all this time. as was mentioned previously about "gremlins", it turned out to be that, before i even took the panel off, the window started mysteriously working again.

so i left it alone all this time.

now, the front passenger window, and the rear drivers window have stopped. i know about the fuses being "criss-krossed" like this, but all fuses are intact. hmmmm..... what could be my problem now? my realy after all? possibly related to my water leakage in some way? please advise...
Even if the fuses are intact the points might have corroded. Check them again, for perfection's sake [:D]

Remove the fuse, check for corrosion on fuse and contact points, clean if necessary. If both clean, put back fuse and check if windows work already.

If still not working use a different but new fuse.

If still not working then it's not fuse.
G
will do. later. now im gonna continue "benzworlding" for a while first. [:D][:D][:D]
karugs - 4/9/2005 8:46 AM

Even if the fuses are intact the points might have corroded. Check them again, for perfection's sake [:D]

Remove the fuse, check for corrosion on fuse and contact points, clean if necessary. If both clean, put back fuse and check if windows work already.

If still not working use a different but new fuse.

If still not working then it's not fuse.
this is very true.. i had some problems with fuses on my merc.. you look at them from the front and they look good.. then you remove them and if you check them thourouly you will see that the top and bottom of the fuse corrodes and detaches itself from the fuse in the middle. so sometimes it works, and sometimes not. this happened specially with one of the fuses.. the one which controls the brake lights, rev counter, dash, etc..

but if you're not getting supply at the fusebox then it must be something else. i'm not sure if the relays are before or after the fuse, but i would replace them anyway.. they do get tired after all these years. i had also changed my switches as well when i had the window problem!
Turns out that's just what it was. I fell victim to the bad fuse number 12 syndrome.
Fuse 12 supplies power to operate the window relay (as well as the 'formentioned lights, tach, etc.).

Thanks.
I also had the same problem. Its the fuse. Mercedes is very wierd. There is a fuse for the front right window, and the back left and visa versa. My windows also stopped going up. It was the window swtich. If you cant get your window to close, flip the switch around (say your back drivers window doesnt work, flip the switch so the front drivers window switch is facing the back). Good luck!
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