Strange electrical problems

[paolo]

(J reg W200TE)
Just started getting some odd electrical behaviour involving both passenger side windows and the sunroof, all completely random. examples:
If I open the front window, then it won't come back up, the sunroof opens part way, then the front window will come up and the sunroof won't close.
Open the rear window, then close it, the front window decides to open.
Whilst driving along, the sunroof decides to part open but will not close.
This behaviour doesn't always happen, but when it is happening I have noticed a chattering coming from the sunroof motor, but I guess it could just be trying to open.
Anybody have any idea what ius going on??

 

[C220GJS]

The common factor in all the systems you mention is the comfort control unit which is an electronic unit mounted,I think, under the false floor in the luggage area of your car as shown No.5 here;http://www.detali.ru/cat/oem_mb2.as...+++717.412&CT=F&cat=15U&SID=82&SGR=590&SGN=17
There are wiring connectors into this unit which are prone to corrosion because of damp in this area, cleaning the connectors with contact cleaner and drying out the area may help with your problems.Also there is a comfort switching relay No.23 in the diagram, you could check ,it seems to be around the dash panel area.
Sorry I can't be more specific with locations, maybe someone with more experience of your car will help.

 

[paolo]

Can't find the comfort module mentioned in my haynes manual, also I don't have a false floor, it's an estate with the rear facing seats.

 

[paolo]

Should add that after looking up comfort control unit in earlier posts, my windows open and close with the key in the door as they should.

 

[Bolide]

It's probably under the carpet under the rear seat squabs

Nick Froome
www.w124.co.uk

 

[C220GJS]

Comfort switching relay is no.89 in this diag.;http://www.detali.ru/cat/oem_mb2.as...+++717.412&CT=F&cat=15U&SID=54&SGR=040&SGN=03
It also controls window regulators and sunroof.