My C5 has been in the garage for almost a year. I took it out in early July and now I'm having power window problems. I posted this in the Tech section about a month ago, but didn't get much of a response, so I'm hoping someone in the General section will have some advice.

Shortly after driving my car, both windows became stuck in the down position. At first I thought it was the driver side switch, but the passenger side doesn't work either. I do not hear a clicking sound when I push either side button.

The windows were stuck in the down position for a few days and then started working again. This lasted for a couple of days until the problem came back. Both windows became stuck in the down position again.

I recently took the car in for a new harmonic balancer and I asked the mechanic to check the windows. The mechanic couldn't find the problem. He told me he was able to get my windows up, but not by using the window buttons. I believe he sent power directly to the window motors. He suggested I take the car to an electronics guy. My windows are now stuck in the up position.

I should add - my battery is brand new.

Any thoughts on what could be the problem? I tried the Fonzi method of banging on the door near the handle, but this seems to be more for when the problem is on one side, not both. Could the wire harness inside the accordian affect both sides? If he was able to get the windows up by sending power directly to the motors, does this eliminate the window motors as the problem?

As always, any help is appreciated. Thanks.

 

I'd still be thinking relays in the door lock modules.

Any chance of borrowing a good module to check the circuit is good. If you put a known good module in there at least you identify where the problem lies. Is it wiring or module?

I'd say its unlikely that the connectors in the door are the problem as neither doors are working.

 

Since it is an intermittent problem I'd suspect a loose ground. Have no idea where it's located but I'm sure lots of folks here will chine in. I'd also say the motors are good if power directly to them worked. Did the guy run separate ground wires along with power to the motors?

 

Maybe not. When the relays begin to stick the symptoms are random.

The left hand door grounds at G201 and the right at G202

 

Have the window regulators every been replaced? It's well known for them to get stuck in the up and down position. You can try s simple regulator solution by holding the window switch in either the up or down position; whichever way you want the window to move. Hold the switch and slam the door at the same time. This may take a couple tries but it will usually free up a stuck regulator. If this works; then the regulators are on borrowed time. They will eventually fail completely. GM has redesigned the regulators at least twice over the years to try and fix this problem. On another note; they also recently redesigned the door control modules. Now when ordering one door module from GM; you must order both so the car will have BOTH upgraded units in the car.

 

I don't know if I can say the problem is currently intermittent. The worked, they stopped, they worked, they stopped and that’s it.
They haven’t worked for about a month. I do have some of the symptoms of a ground problem. I get the traction control warning
when I hit a bump sometimes. I just find it strange they both stopped working at the same time.

 

I'm not getting the clicking sound when you push the window buttons and from some of the threads I read, this usually happens to one side at a time, not both. I've tried banging the doors a couple of times, I've also tried jiggling the wires inside the accordion sleeves on both sides.

I should add, I just noticed my power door lock button on the driver side only controls the driver side right now. The passenger side does the same thing. It only controls the passenger side.

Maybe I should inspect the connections inside each of the accordion sleeves. They're a little tough to get to in my car, but I thought I read a thread previously that stated they can get corroded.