I have a 91 S$ that just came back from the paint shop. Looks great, but the windows and sunroof are dead. I read other posts about similar problem and have not found the solution.

I get voltage at the fuse panel when the switches are pressed. No voltage at the motors. Looking at the wiring diagram, it doesn't look like there is a relay, like in older models. There is a control unit for the power windows/roof, but where is it? The wiring diagram doesent say.

Any help is greatly appreciated.

Thanks
Paul Farmer

 

Sometimes it's the fuse. Even if it looks good - change it anyway.

 

Did they remove /replace window seals during the paint job?

 

Paul,

The control unit is under the drivers seat on US cars.

Did you check fuse 18?

 

Thanks for the response. The seals were taken off for the paint job. Im putting them back on today, some new. I replaced Fuse 18 with a good one, and still no luck.

Thanks Paul Farmer

 

I forund the control box, opened it and found one of the relays burned around the contacts. When the box is connected, there is 13 volts to the two wires that lead to the motor. Should there always be power? Is the motor a neg ground to the car? Im afraid that the bad relay may have caused the power to stay on and the motors to burn. Can this be?

Thanks

Paul Farmer

 

Paul,
I asked a similar question of several people at the 3rd Coast.
Someone had posted that my problem might be a relay problem -sunroof-.
But using the owners manual fuse and relay chart I could not locate a relay. And on the 82' MY the fuse for the sunroof is apparently the only safety in the circuit -I'll look for a controller tomorrow-.
In your post you mentioned a relay ... is it on the relay panel or in conjunction with the controller?
Unless there was a change on the later model cars or my ignorance - very possible - I don't see a relationship between the sunroof and the window motors. The controller maybe?
TIA

 

The '91 and later cars have the "new" control unit operated windows and sunroof. One of the features is: you can close them with the key in the drivers door.

Paul, My control unit started making a moaning sound and burned the contacts on one of the six relays. I cleared away all of the melted plastic on the relay contact and could see the relay arcing and trying to melt itself again. I resoldered all solder connections on the circuit board and all is OK for the last 6 months. The only remaining abnormality is: all of the relays click once every time you open a door, but it dosen't seem to hurt anything.

The control unit is attached to 30, so it always has power, I guess for the key function to work with the ignition off.

The window motors are not connected to ground. The polarity is reversable by the relays depending on weather you want the window to go up or down.

Your motors are probably OK. The motors probably still have circuit breakers built in, to protect them. Make sure the contacts on that relay are making physical and electrical contact. Resolder the circuit board and see what happens. Test with the cover off to make sure the relay is not eating itself again. One of the big three told me "I sell a lot of those control units"