W124 electric window problem

paolo

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I have a 1991 W124 estate, that has been sitting for some time.
The front passenger window motor is permanently running in the up direction, I have checked the wires in the door and they are permanently live. I have removed the console switch, but this has made no difference and checked the relay under the bonnet, which seems fine as the other three windows and sunroof operate correctly. Decided to try and find the comfort module.
Found it!
Had to cut a hole in the carpet under the rear seat squab though.
Relay #6 keeps locking up in a closed position, all the others working fine. If I wedge it open, then the switch works to open the window, but if I manually close relay #6, then it also blows a fuse. I have checked the earth wire to the motor for continuity and it is fine, so I guess this module must be faulty, doesn't look cheap to me and I suppose it's not repairable, (If I knew where/what the fault was in the first place!)
I don't suppose there is any way to test it before replacing it?
 
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paolo

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What do you mean by door switch?
 

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Later cars had a window switch on the door as well as the console
 
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paolo

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The front windows only have the switches on the centre console on my car.
 

television

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I do have the circuit diagram of the comfort box

Tell me please on the comfort box,,,can you disconnect the outputs to the windows plug just leaving the power going in, to see if the relay still closes
 
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paolo

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Are the outputs the large plugs on the outside?, A and B
 

television

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I have been looking at the wiring harnesses and this would not work they all have live feeds.

I can send the file to you but it is too large to go by Email,,it will only go by MSN
 
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paolo

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unfortunately I'm not on MSN
 

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I can try it by Email depends on the size of your box
 
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paolo

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Just sent you a PM with my email, how big is the diagram, (in MB)
 

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It has now left my box it is a retro fit paper,,but contains all of the circuits
 

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an over complex system and frustratingly difficult to work with to achieve diagnosis. can give all sorts of annoying and intermittent symptoms, so good luck.
 
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paolo

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Just checked it over, (R13 is good) and I can't see any problems. I guess my only option is a replacement.
The part number on mine is 124 820 32 26, I have found one on ebay, that says it's for a W124, but the part number is 202 820 09 26 is it compatible?
 

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I can see that R13 is good. You have 4 circuits here all the same,,if there is 4 relays, then all 4 should measure up the same, and that is the components all around them. I see it uses a TC4049,, they are standard chips.

If you can establish a 12volt live in,,you could join it up to see if that relay closes with nothing else plugged in.

One side of the relays will be the live one,,so does one of the spool coils read different to the others,,the faulty one for instance.

Sorry it a jumbled reply

I cannot say about the 202 version, though it is listed here for a 124 TE 300

http://www.detali.ru/cat/oem_mb2.as...GM=717.433&CT=F&cat=15U&SID=82&SGR=590&SGN=17
 
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paolo

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OK, so I have checked it out with all wires connected. For the front right and both rear windows, relays 1 to 4, 7 & 8 all work correctly. When the front left switch is pressed down, relay 6 activates and stays closed, even when the switch is released, I can only release it by physically pushing it open, when it stays open. When the switch is pressed up, nothing happens, relay 5 should close, but it doesn't.
 
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paolo

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So should I replace it? Does anyone know of a repair service for these modules?
Do you think it could be anything other than this?
 

television

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So should I replace it? Does anyone know of a repair service for these modules?
Do you think it could be anything other than this?

I can test all of the components for you
 

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