Wierd power window/sunroof problem
 

My 1992 300E Sportline edition, has started to do a very quirky thing with the power windows and sunroof, when I started the car this morning the sunroof automatically retracted, and then would not respond to the switch when I tried to close it, additionally the windows seem to be tied into this problem. I'll start by saying that the passenger side front and drivers side rear seem to operate normally. When the drivers window button is depressed the window opens completely like the way a newer Merc would not the way this 1992 was intended to open and then after it's down it doesn't go back up. The passenger side rear window is also very quirky it will respond only if the all the other windows are down, and getting it back up is a trick. Oh! and the sunroof closes only when either the passenger rear or front window switch is depressed for the up direction. So I have to follow a very strict protocal in order to get the car closed up, it's a very frustating problem especially when the weathers foul. Can anybody help me find where this Gremlin lives?

Thanks

Tucker

Hey Tucker, my 92 300E did that once! There were times that I could've sworn I opened the sunroof only to find it had closed itself... hehe I traced my problem to a corroded connector inside the trunk near the attenna motor. Its a black square connector with female pins inside. I took the connector off, cleaned the pins and compressed them some to ensure contact with the mating pins. Conductive grease helps too!

There is a computer under the left side of the rear seat that controls the S/Roof & window operation, have replaced several of those ECUs. Of course make sure that all of the wires are connected & clean the connectors.

I have not yet had a chance to do some sniffing around and cleaning up terminals and connections. But if the out come of that is not the fix, could you let me know what the name and part number of that ECU that you mentioned is. Thanks,
Tucker