W202 electric window problem / comfort control module fault

[LastMinute]

Ian's got a 1995 W202.125 C250 Diesel in The Works with a defective front passenger electric window. We've checked the fuse, the switch, the motor, the wiring and the comfort switching relay, and they're all OK - so that leaves the comfort control module (= box with 8 relays [one 'up' + one 'down' for each window] and some electrickery) as the prime suspect. This is an early W202 - i.e., before the days of CAN bus and door control modules.

There appears to be a stray 1.4V across one of the relay coils. It's not enough to pull the armature in, but is enough to hold it in once it's there. The coil resistance (measured in situ in the circuit assembly) is the same on the dodgy relay as on all the others.

A new module is £192, so we're looking for a lower-cost solution.

Any ideas for further testing or repair of the existing module?

Cheers

 

[Dec]

If the are open, do the other 3 windows and sunroof, (if fitted) close automatically when the car is locked via key fob?

Dec

 

[BlackC55]

There is nothing that I know of. I will have a look to see if I have a second hand one. If you dont hear back I havent got one.

 

[LastMinute]

If the are open, do the other 3 windows and sunroof, (if fitted) close automatically when the car is locked via key fob?

Yes.

 

[GazCaff]

If the car is still there on Sunday I could pop up to allow you to borrow a known good unit for testing

I know Ians sacked me as his sparky , but my car is due an oil change (according to my belts and braces service schedule it is anyway) so I could kill two birds with one stone and I'm always happy to lend a hand if I can.

 

[LastMinute]

Cheers, Gaz, but the customer is collecting the car tomorrow (and exchanging it for another toy for Ian to play with ).

If your "known good unit" is the one fitted to your car then you might want to think again about the offer because it's not a quick job to get it out. Empty boot, remove spare wheel, move battery, unbolt module, disconnect wiring connectors... And refitting is the reverse of removal, of course

 

[GazCaff]

Cheers, Gaz, but the customer is collecting the car tomorrow (and exchanging it for another toy for Ian to play with ).

If your "known good unit" is the one fitted to your car then you might want to think again about the offer because it's not a quick job to get it out. Empty boot, remove spare wheel, move battery, unbolt module, disconnect wiring connectors... And refitting is the reverse of removal, of course

The effort invloved in removing it wouldn't have bothered me. I've been mulling the problem over since posting but I cannot offer any new advice without seeing the car. The only thing I can suggest is that there is possibly a bad earth or a dry joint somewhere which is causing the stray 1.4v.

As for fixing snapped electric aerials though, I've found I'm quite handy at that!

 

[LastMinute]

there is possibly a bad earth or a dry joint somewhere

We tried wiggling the circuit board with everything connected but it didn't make any difference. (Relay failed shut did not open.)

The wiggle technique did reveal a dry joint on the combination relay module, however, so at least we managed to fix the rear screen heater...

 

[Dec]

“If the are open, do the other 3 windows and sunroof, (if fitted) close automatically when the car is locked via key fob?”

The reason for my question is that I just had my car serviced at main dealer, I requested that the fix/reprogram the windows/sunroof so that the close automatically when the car is locked, the use to do this when I first got the car.

The said this cant be done until the rear passenger window which is not working is replaced, apparently there is a short in the motor and it is interfering with the unit that controls this function. I thought this might have some relevance to your problem.

Dec

 

[LastMinute]

Hi Dec,

I see what you were getting at but it sounds like a different problem. In our case the motor is fine, but the control module is not commanding it correctly.

I should add that when I say the convenience closing works, that's with the motor for the offending window disconnected. I expect that if you disconnect your defective motor the other windows and sunroof should close with the key, as before.

 

[Dec]

Hi LastMinute

Disconnected at motor as you said, but didn’t solve problem, disconnected battery for an hour and after reconnecting battery, I reset the windows one-touch control, which is working O.K., as before, this still didn’t solve the problem. Not to worry, I can live without automatic closure for now and the window never gets used anyway.

Thanks for your help.
Dec

 

[Shala]

Dec, hav you solved the [rpnlem with the auto window?
my auto-electrician said you hav to manually take the window down until you hear a claick. then you press down for auto closure. same again. take window up manually by holding down the button. then press the button after hearing the click. this re-programs auto-clusure.

Shala

 

[Dec]

Hi Shala
I did all that but that was not the problem if you read post#9 you will see it was to do with TOTAL (comfort) closure that is when I lock the car all windows that are open close automaticaly, you are talking about reseting the one touch controle which is not the problem.

Any how I have since replaced the faulty motor but the TOTAL closure now needs to be reprogramed, but that means STAR + Cash so can live without it for now.

Dec

 

[Shala]

wow! my car doesnt even have total closure

 

[BlackC55]

wow! my car doesnt even have total closure

Yes it does.

When the windows are open just press the lock button and hold it down and point it to the door handle until the windows are up

 

[Shala]

would mine have that? I'm gonna check it out

 

[television]

would mine have that? I'm gonna check it out

Thats what the man said so have fun.

 

[Shala]

WOW guys. thats awesome. got my car in february 2006 & I never knew this. You wont beleive the number of times I left the window open & went back in the car to close them

I'm definitely gonna make use of this feature. already showed it off to my wife , my friend & my brother. But my brother went one better & showed his BMW roof go down on the touch of a button. Always someone that spoils the fun eh?

I love MBClub

Cheers

 

[television]

WOW guys. thats awesome. got my car in february 2006 & I never knew this. You wont beleive the number of times I left the window open & went back in the car to close them

I'm definitely gonna make use of this feature. already showed it off to my wife , my friend & my brother. But my brother went one better & showed his BMW roof go down on the touch of a button. Always someone that spoils the fun eh?

I love MBClub

Cheers

Keyless go is nice for the show off bit, when you just walk over and put one finger on the door handle and it unlocks. When kids ask if they can do it I say OK hold my hand and it will do it for you.

 

[Shala]

Lol!!!