DeWolf

Hi Guys,

Can't seem to figure out whats going on. It's a 1990 model and the windows and sunroof just stopped working. Fuse is ok and tested good but I replaced it anyway. Does the window control under the seat operate the sunroof as well? I noticed after buying the car that if my wife and I went to put the windows down at the same time one would stop. Something is amiss.

MainePorsche

Yes, on your MY there is a Power Window/Sunroof Control Unit. I am unfamiliar with debugging window/sunroof issue(s) that have this control unit. Others will be chime in.
Best Wishes

MainePorsche

Bump for this fellow.
Sounds like he's having a tough go by some of his postings in Bill Ball's 90 S4 Window thread.

MainePorsche

Just throwing some old threads here. Maybe you'll find a pearl somewhere that'll help.

https://rennlist.com/forums/928-foru...oof+controller
https://rennlist.com/forums/928-foru...oof+controller
https://rennlist.com/forums/928-foru...oof+controller

DeWolf

Yeh thanks mate, I've been through those as well.

Schocki

Do you hear a faint clicking from under your seat when you are pressing the window or sunroof buttons?

Have you tried to lock the car from the outside (driver side) and close the windows with the key from the outside?

Edit: BTW yes, the little black box controlls the sunroof too.

DeWolf

Yes I've pulled the controller out and can hear the relays clicking when I press the window and roof buttons. Just can't work out why I only have 2.6V where it should be 12V. Don't even know where to begin to look.

Schocki

The relay contacts inside are spotless clean? Take a close look, often you will see pitting on the contact surface.

Mrmerlin

take the controller box apart,
put deoxit 100 on the contacts,
let the box sit for a few hours, also put deoxit on the fuses,
and then try the unit

DeWolf

^ I'll give that a try tomorrow. This is first 928 I've had that has given me any trouble at all. Mongrel of a thing!

Alan

You did replace fuse #31 correct? check that you get 12V+on the bottom fuse terminal, probe into the open dimple on the body down to the fuse blade with it still in place

Alan

DeWolf

Thanks Alan, I will try when I get home.

DeWolf

Ok, have 12V at the bottom of the fuse. I should add that the car has had an alarm fitted and remote central locking. The PO said he has never had an issue with it. It was installed by Bruce Buchanan.

MainePorsche

Hmmm...
You could have three complicated solar systems colliding in an already complicated universe...
It is good that Alan has been here, and is aware of your thread.

soontobered84

Are we not thinking RELAY at all here gentlemen?

Nevermind.

I answered my own question after I posted. There doesn't appear to be a relay for the sunroof and windows as there is in the earlier cars.