Power Window Buttons not working

[Andy Aloia]

Hello all,

 

I have spent the length of today trying to find an answer on Google and by extension this website. Most of the articles I have come across reference similar, but not the same problem. (Windows not ducking)

 

I own a 1999 996, I recently replaced the starter in my vehicle which required removing the battery. Upon re-connecting the battery none of the power windows work via the rocker switches in the center console or overhead console (Driver, Passenger, Overhead). However, whenever I open the doors, the windows still duck properly. Additionally, I can put my key into the door and hold it to the left/right and the windows will go up or down depending on direction. Prior to disconnecting the battery everything operated as intended.

 

I checked fuse C3, it is in working order.

I can hold down the window up or down buttons, but nothing happens. 

I have disconnected the battery again thinking that maybe there was something I missed. Has no affect on windows.

 

Does anyone have any experience with this issue? I am at a complete loss.

 

Thanks everyone.

[Ahsai]

How about fuse D1?

[Andy Aloia]

How about fuse D1?

 

Fuse seems to be in good working order on visual inspection.

I also checked B5, and it also seems in good order.

Edited October 21, 2014 by Andy Aloia

[Ahsai]

How about fuse B6?

[Loren]

Always check fuses with an ohm meter - it can and will save you a lot of time looking elsewhere.

[Andy Aloia]

How about fuse B6?

B6 is in working order.

 

I also checked B1 (convertible top unit control) even though I am a non-convertible. All of the fuses seem to be in working order.

 

Is there anyway to reset the window control module? 

[Ahsai]

Strange indeed. The control module should be reset when you disconnect the car battery. Can you use the key to roll the window half way down, then try to use the center console switches to operate the windows?

 

I wonder if it has anything to do with the window reset procedures normally performed after battery re-connection. Obviously your windows get power and SOME inputs from the control module work. Just not the inputs from the switches.

[Andy Aloia]

Strange indeed. The control module should be reset when you disconnect the car battery. Can you use the key to roll the window half way down, then try to use the center console switches to operate the windows?

 

I wonder if it has anything to do with the window reset procedures normally performed after battery re-connection. Obviously your windows get power and SOME inputs from the control module work. Just not the inputs from the switches.

Exactly why it is so strange to me. First time I have ever seen this. 

 

I have tried:

I turned key to unlock position put windows all the way down. Disconnect battery negative, wait 30s, reconnect battery, get in car, close door, key in ignition to on position, press window button, no result.

I repeated the steps attempting the following ways.

Put windows at halfway from up position. (turn key to unlock)

Put windows at half from down position, (turn key to lock, then unlocked car before disconnect)

Put windows at Up position

Put windows at Down position.

 

All results in no response from any button.

[Andy Aloia]

Always check fuses with an ohm meter - it can and will save you a lot of time looking elsewhere.

Going to do that now! Almost overlooked this post as I replied to Ahsai.

[Andy Aloia]

Always check fuses with an ohm meter - it can and will save you a lot of time looking elsewhere.

 

 

Checked all fuses discussed. All were under 2 ohms. Seem to be in working order...

 

To add I have left the battery disconnected for about 30 minutes now. I had read elsewhere that some 996 owners disconnect both terminals on the battery and then short the battery lead wires with a jumper cable. Is this a valid thing to try?

 

I'm kinda at a loss for things to try!

Edited October 21, 2014 by Andy Aloia

[Andy Aloia]

Just doing some wondering, could this possibly be related to a battery issue?

I measure 12.5v across the poles with the battery completely disconnected from the car. With the car on and running idle it was around 13.9-14.2v That seems normal enough, but this is my first Porsche.

 

Would the alarm system prevent the windows from functioning properly via the console buttons?

My key fob button does not work, so the only way I can activate the alarm is via turning the key in the door to the right twice. It gives 1 honk, however the doors stay locked. (I assume that is activation verification?)

 

Just trying to think out of the box.

 

 

Thanks for the help again guys, you have been awesome.

[CabrioArtie]

Can't say this is your problem, but I had the same exact issue. I could even open/close the cabrio top and the windows would open and close, but the window switches would not function.

 

Went for a State Inspection, went home and everything was working properly. Put the car in the garage and went into the house for about an hour. Came out to the car to run an errand and the window switches would not function at all.

 

No fuse issues. Nothing I did, would fix it.

 

Took the car to my Indie and after some diagnosing, he found that the Immobilizer module had shorted out. Replaced the module and everything was good once all the keys were reprogrammed. Hope this isn't your issue as this isn't a cheap fix. 

[Andy Aloia]

Can't say this is your problem, but I had the same exact issue. I could even open/close the cabrio top and the windows would open and close, but the window switches would not function.

 

Went for a State Inspection, went home and everything was working properly. Put the car in the garage and went into the house for about an hour. Came out to the car to run an errand and the window switches would not function at all.

 

No fuse issues. Nothing I did, would fix it.

 

Took the car to my Indie and after some diagnosing, he found that the Immobilizer module had shorted out. Replaced the module and everything was good once all the keys were reprogrammed. Hope this isn't your issue as this isn't a cheap fix. 

 

Boy, I really hope it is not that bad. :( I should get my ODB2 scanner in today, I'll see if there are any codes.

[Ahsai]

 

Can't say this is your problem, but I had the same exact issue. I could even open/close the cabrio top and the windows would open and close, but the window switches would not function.

 

Went for a State Inspection, went home and everything was working properly. Put the car in the garage and went into the house for about an hour. Came out to the car to run an errand and the window switches would not function at all.

 

No fuse issues. Nothing I did, would fix it.

 

Took the car to my Indie and after some diagnosing, he found that the Immobilizer module had shorted out. Replaced the module and everything was good once all the keys were reprogrammed. Hope this isn't your issue as this isn't a cheap fix. 

 

Boy, I really hope it is not that bad. :( I should get my ODB2 scanner in today, I'll see if there are any codes.

 

 

A generic OBDII scanner will not be able to retrieve anything related to the immobilizer/alarm though. You need Durametric at a minimum.

[Andy Aloia]

 

 

Can't say this is your problem, but I had the same exact issue. I could even open/close the cabrio top and the windows would open and close, but the window switches would not function.

 

Went for a State Inspection, went home and everything was working properly. Put the car in the garage and went into the house for about an hour. Came out to the car to run an errand and the window switches would not function at all.

 

No fuse issues. Nothing I did, would fix it.

 

Took the car to my Indie and after some diagnosing, he found that the Immobilizer module had shorted out. Replaced the module and everything was good once all the keys were reprogrammed. Hope this isn't your issue as this isn't a cheap fix. 

 

Boy, I really hope it is not that bad. :( I should get my ODB2 scanner in today, I'll see if there are any codes.

 

 

A generic OBDII scanner will not be able to retrieve anything related to the immobilizer/alarm though. You need Durametric at a minimum.

 

 

Ah, I'll ask my local guy that specializes in foreign cars if he has one. If not, I'll probably look into purchasing one. Unfortunately the closest Porsche dealer is about an hour away from me.

Edited October 22, 2014 by Andy Aloia

[Hilux2400]

I would have thought that there is a relay for the windows, but I don't know where it is. The main relays in my 996 are under the plate behind the rear seats.  I carry spares for the "53" relay as they are quite simple switches, but I would think that the window relay has several internal circuits.

 

H 

[Ahsai]

Per the wiring diagram, there are no relays. The alarm control module connects to the window switches, which in turn connect to the individual window motor units. Looks like there are power/overload protection circuits inside these motor units as they take multiple inputs to activate the windows including direct inputs (comfort OPEN/close) from the alarm control module. Since both of the window switches don't work, it's likely something common to both - fuses or the alarm control module.

[Hilux2400]

Thanks Ahsai that's good info.

 

Could it be a problem with a common earth point?

 

H

[Ahsai]

There's one common ground point (GP4) for both switches around the instrument cluster area. I can't imagine how that gets disturbed though by R&R the starter.

[Andy Aloia]

I called several local shops, unfortunately and expected, nobody had equipment to connect to a Porsche. Looks like I'll be ordering a Durametric. I'm sure it will pay for itself over the course of my ownership of the vehicle.

 

I have not messed with the instrument cluster area. I'll be removing the switches tonight to try and verify that the ground connection is good.

[Andy Aloia]

Well I took the car for about a 20 minute drive last night, and of course not thinking I went through a drive through to grab a drink for my friend and I to split. Sure enough, the window rolled down! I was awestruck when I realized what had happened. The Driver, Passenger, and Overhead windows all began working! I parked the car and left it overnight (about 12 hrs.) I checked it again 5 minutes ago and all of the windows are working.

 

I have no idea what happened and it is super annoying to spend so much time diagnosing to only have it start working randomly. I have not ordered the Durametric yet as I was going to try replacing the fuses just in-case those were the problem.

 

The only thing I think that it could have been was something to do with the alarm module. I'll be checking it regularly for the next week, and if it holds I will call it "fixed magically". If it happens again, I'll be sure to get a video.

 

To everyone that commented, thank you so much for your help. Honestly, I am appalled at the amount of support and dedication you guys have for these cars. I only hope that I can be helpful one day and give back. 

Edited October 23, 2014 by Andy Aloia

[Ahsai]

Isn't it great that these cars fix themselves? :)

[Ronnie38]

Watch out my 2001 C4 Cab rolled all of it's windows down during a thunder storm, had to send the alarm CPU to the CPU Doctors for replacement. Why would you mount a CPU on the floor under the drivers seat? I now park it in the garage  or put on the hardtop. checked the drains all were open.

[Ahsai]

If it happens again, maybe worthwhile to disconnect the battery, unplug and clean the connector contacts of the alarm module with Deoxit (under the passenger seat) and re-plug the connectors.

Edited October 23, 2014 by Ahsai

[Andy Aloia]

If it happens again, maybe worthwhile to disconnect the battery, unplug and clean the connector contacts of the alarm module with Deoxit (under the passenger seat) and re-plug the connectors.

 

Ha! I took the car out for a brief drive yesterday to a movie theater and back. Sure enough, on way to the theater the windows did not roll down. On the way back they worked just fine. It very well may be a connection/contact issue. I will keep you guys updated once I have cleaned the contacts and connections.

 

I also ordered a Durametric to further check everything out and clear any codes that may exist in the ECU/ALARM.