Power windows dead - anyone know of a step by step diagnostic procedure

[Doug427]

Just bought a '02 S. The power windows are completely dead. The only sign of life is a tiny drop in the passenger side window when the door opens, maybe 1/4" at most. Other than that, nothing. I checked the C3 and D1 fuses. Both are good, and there is power at the respective fuse terminals. As best I can tell the "immoblizer" has not been wet. When I raised the top a little while ago, I thought I heard a click or thunk inside the drivers door, but I can't be certain. I know some people mention interior light issues when discussing power window issues. My interior lights are not working either, if that matters.

There some info on the forum here, but it's kind of scattershot. Is anyone aware of a real step by step "try this, then try this next, then this....." type of organized diagnostic procedure? Sort of a "check for voltage here. If it's there, move to this component next and check for voltage here", and so on. Electrical is my weakest area. I know the windows were working a week or two ago, and now they're not. Both are dead. Is there a relay somewhere?

I'm lost and don't know where to start. Any help at all will be gratefully appreciated.

[Geof3]

Try your key. If you put the key in the driver's door, turn it left and hold the windows should go down. If they do then they are functioning, but there is a glitch perhaps at the switch (may be bad). If they don't, might be the immobilizer, and one of the electrics gurus here would have to chime in.

[particlewave]

Did you check the immobilizer yet? It's fairly easy to pull out, open up and check visually.

[Doug427]

Originally Posted by Geof3

Try your key. If you put the key in the driver's door, turn it left and hold the windows should go down. If they do then they are functioning, but there is a glitch perhaps at the switch (may be bad). If they don't, might be the immobilizer, and one of the electrics gurus here would have to chime in.

Tried the key. Dead on both doors. Locks move, windows don;t respond at all.

[Geof3]

Bummer. I think there might be a relay if you haven't already looked at that. It could also maybe be your ignition switch, it can cause all sorts of weird issues, though I'm not sure if windows are part of that equation.

Have you tried disconnecting the battery for a few minutes to see if they reset? Does your alarm/central locking work? If it does, does it beep or anything on actuation? It shouldn't. All you should see is your lights blinking and central locking do it's thing. If it beeps, there is a problem. In the owners manual there is a section that explains the beeps and what they mean. I just don't remember or have the manual handy.

Also, you mentioned this happened after raising and lowering the top. Have you tried it again? It could be the center latch isn't completely closed, or the top isn't quite properly seated. Open and close the top with the doors open, then see if your windows move down then up upon lock.

[particlewave]

The top position won't affect window operation.
The window relays are soldered to the immobilizer board, as I mentioned in the OP's other thread. If the windows drop when the top latch is pulled, the relays are fine. The problem most likely lies between the switches and the immobilizer.
I suspect bad connections or corrosion at the immobilizer connector, but no way to tell if the OP won't do the legwork, so I think I'll step away from this one.

[Geof3]

Originally Posted by particlewave

The top position won't affect window operation.
The window relays are soldered to the immobilizer board, as I mentioned in the OP's other thread. If the windows drop when the top latch is pulled, the relays are fine. The problem most likely lies between the switches and the immobilizer.
I suspect bad connections or corrosion at the immobilizer connector, but no way to tell if the OP won't do the legwork, so I think I'll step away from this one.

OOOH... didn't realize we were answering the same questions... Yeah, gotta jump all the way in for sure!

[Doug427]

Originally Posted by particlewave

The top position won't affect window operation.
The window relays are soldered to the immobilizer board, as I mentioned in the OP's other thread. If the windows drop when the top latch is pulled, the relays are fine. The problem most likely lies between the switches and the immobilizer.
I suspect bad connections or corrosion at the immobilizer connector, but no way to tell if the OP won't do the legwork, so I think I'll step away from this one.

Particlewave, I'm not unwilling to do the legwork, I can promise you that. I greatly appreciate the help. I've been on the road and unable to get to the car until Sunday night. This is my first Porsche, and all the quirks and terminology can be quite overwhelming. If I understand you correctly, I need to remove the drivers seat, and remove the immobilizer and check all the connections on it to make sure they're clean, and obviously clean them as best I can while there. I assume I do all this with key off. Is there anything else I should be checking for on the immobilizer box while I have it out?

[particlewave]

Yes, remove the seat, check/clean the connections and open it to visually check the circuit board for corrosion.