At first, it was happening to my passenger's window. It can open just fine. And when I try to close it, I push the window button till it reaches half way high, it is supposed to close all the way up automatically. But when it reaches 3/4 height, it is bounced back and stopped somewhere in the middle. I push the button again and it can just stop at 9/10 position. I have to push for the third time to close it completely.

Today, same thing happened to my driver's windows.

What's happening?!

 

Not sure if this will help but maybe try resetting the windows - I've attached the page from the owner's manual.

 

i remember this happening on the sunroof on my 996. there is a "training" procedure a sequence of opening and closing that you need to do to get it back on track. usually happens when you disconnect the battery.
i got the info from renntech.
http://www.renntech.org/forums/index...=train+sunroof

 

Thanks for the page attached. I guess that particular page is referring to the re-setting when the window is raised automatically when the door is closed. Mine can raise to the correct end position when the door is closed. No problem with that.

My problem is I can't close the window in one shot, but three!

Is the window motor failing?

 

Thanks for your input. For the time being my sunroof is working fine!

 

As I said, wasn't sure this would help...but wouldn't hurt to try it.

 

No luck! Tried to "train" the window, but the problem persists!

I took a video of the window's movement (sorry for the poor quality and the clockwised direction as cell phone was used). Any clue?



Key notes:
1. Downward movement no problem!
2. In the upward movement, there are two hiccups. First bounce-back at reaching 3/4 height, then gets stopped at 9/10 height (nearly closed, you will only see a gap left opened), then fully closed upon third click of the button.

 

It could be a faulty anti pinch sensor. The windows have a sensor that prevents fingers and other things getting caught in the windows. The sensor might be sending false signals to the computer.

 

Which part you are referring to? I attached the page of the power window parts.

 

I don't see anything on the PDF, I would consult your dealer, either parts department or service.

 

Strange, the pdf does look fine. Anyway, thanks!

 

PDF is fine, but I don't see all the window parts. Sorry if I wasn't clear on my last post.

 

Thanks for clarifying. I thought that page includes eveything that the power window system is concerned.

I will check with my local dealer to see if they have any clue.

Thanks again!

 

same exact thing happened to my car. They had to replace the motor. It still happens now but very rarely.

 

Learned from the expert in Design911 in UK (thanks to Graham), that I have tried to reset the power window's one-touch cycle by operating it down-up-down continuously with my finger always on the button (i.e. keep holding the button for the entire process).

This resetting procedure does help, and has resolved "part" of the window problem.

What I say "part" of the problem, I mean the problem is gone once the procedure is done, but it will come back in some occasions. Frankly, I haven't figured out the exact "conditions" on which the problem will re-surface. Sometimes when I have switched off the car and left it there for a while, the problem will occur again next time when I start up the car and try the window.

It doesn't seem to me a mechanical faulty, as it could run just fine after the reset. So I guess it has more to do with the motor programming.

I have run out of clue ...anyone could share any thoughts?!