John,
Once you are in the door its pretty easy to test the motor and decide if a replacement is needed.

The older models have limit switches built right into the motor - not sure exactly how they work - I think they are just a kind of thermal switch that self heat based on drive and esp the extra current when the motor stalls (top/bottom).

The controller under the drivers seat in later cars (89+) controls the windows & sunroof. Its microprocessor controlled and takes the switches out of the high current circuit. It senses current to determine when things are fully closed or open, it only runs one unit at a time but stores keypresses so will open windows/sunroof sequentially in the order you click. It drives to motors via relays - hence the clicking when operatingreferred to above.

ROW/Euros have express close on drivers window as well as express open on all - as with USA cars. It also closes all in sequence when you lock and hold the key - this makes the same from keyless entry easily feasible too. It extends operation until a door is opened with ignition off and on ROW/Euro the controller is also temporarily active whenever the doors are open - if you have a Euro and work on the door motors this is worth remembering (pull the fuse).

Some dislike the sequential opening thing - it takes a long while to open everything and most cars don't work this way...

Alan

 

I'm in the door today troubleshooting the driver's side window.

The window controller makes a clicking sound when I press the switch, but I'm not getting 12 V to the motor connection. A test with a replacement motor does not power the motor.

Is there a fuse/relay on the CE board that may be the problem? I haven't opened the CE yet.

Any ideas?

 

Check the plug on the window module under the drivers seat - more the seat all the way forward - under the metal cover - is it seated correctly?

There is a fuse for the module - seems unlikley its that if the relays are clicking - fuse 18 on a GTS...

Check both sides of the motor for voltage - neither is a fixed ground.

If the module is getting power and the motor is dead - its either connection on the way (door harness?) or the module has a fault - a relay issue maybe.

I never figured out how ther relays were set up - it seems to have too many... partly due to the sequencing thing and the single current limit sensor... I have a photo of the guts at home.

There are selector relays for L/R sunroof, there are power reversing relays and a retained power relay. if the sunroof & pass work right seems it could only be the selector relay for the drivers side - if its the module.

With the motor disconnected - test for resistance between the motor connections?

Alan

 

Thanks, Alan.

I've discounted it as being the motor - the one in the car tests OK on continuity.

I've pulled the controller and all connections are tight and clean. It's looking like one of the relays within the controller is bad, but it's a sealed box, so can't open it up to try cleaning/adjusting the contacts inside.

 

Randy,
Sorry I wasn't clear - test the cars motor connection for resistance when the motor is disconnected - should be infinite... is it?

BTW you can get the controller apart - its just a bit tricky. there are spring tabs all around the open end - I think the only way to get this out is to cut some of the tabs flush with an x-acto knife. Not all the tabs are needed to keep it in there - its a bit of overkill. I think I cut off the narrow end ones so I could pry the sides out more easily (just from memory).

Check everything else first!

Alan

 

Know anyone locally with an 89+ you can try a module swap with (position it under the guise of a Euro configuration change - you are doing that that at the same time right?)...

Alan

 

Yes, the motor tests open (infinite).

Euro config?

 

Randy - this one (thought you were reading these posts...! )

https://rennlist.com/forums/showthre...eferrerid=6055

You are right there - except for the motor not working...

Alan

 

MY 90+ has the window controller. -89 does not have the controller (according to the Porsche yearly service updates and previous inspection of my '89.)

 

Dave - yes quite right - check that: '90+ not '89+ (too many feature changes to remember!). It was posted correctly in the previous post - should have just read it again...

Alan

 

Hah - my kinda 'mod' - just unplugging somethin'!

I had actually pulled that connector apart this morning before I read your referenced thread, thinking it was a fuseable link or something.

 

To correct my rattley window, I had also bought new window guides that I was going to replace on the driver side since I'd have the door innards exposed.

Course, you need to be able to roll the window down to do that job! So I just buttoned it all back up for now.

 

Randy,

Is this what you need?

On Ebay

 

That's it - thanks. Must have just been listed - an eBay search yesterday got no matches.

 

Installed the new controller module - same problem, dammit! Must be an open somewhere in the harness between the window motor and the controller.