Request advice on my window switch/wiring issues please

[1988coupe911]

I am a new owner of a 1988 911 coupe. The passenger window switch worked very sporadically when I bought it, and initially at least, after moving the switch up and down a bunch of times, it would open and close. Last week the passenger window only worked once in at least 50 tries, and the driver window started experiencing similar issues, though generally reliable. I pulled the switches and cleaned them with no improvement. I boughT new switches and installed them with no change either.

While doing this, I noticed that the window switch wires from the drivers door into the car had been cut and were taped together, so I thought that might be the issue and I cleaned the wires and reconnected. Now, when I activate the passenger side window switch from the drivers door, the fuse blows. The fuse is fine operating the divers window....and I've never had any issues with the sunroof.

Any ideas or help would be much appreciated.

Thank you!

[Bob Kontak]

Welcome to the forum. Odd the wires were cut. Were all of the wires cut leading into the car? They may be cut on the passenger side as well.

You probably just have a wiring screw up. Simple to fix once you find it.

Here is a link to a non factory manual. I think it is a Bentley manual http://www.cannell.co.uk/Manuals.html.

The book is not in perfect order. I just downloaded it. What you need is on pdf file page 86 of 717.

Sketch out the terminal numbers on the switches and the wire colors and test continuity of the wires. It is tedious but doable. I am not an electrician but a multi tester and the wiring diagrams can get you a long way towards solving this.

If you can't download I can post the pic.

[1988coupe911]

Thanks for the quick and detailed post. I wasn't able to download the manual but will try on a different computer tomorrow. I also found it odd that the wires were cut. I will check which ones were cut as well and let you know, but I'd estimate four of the six. Thanks again!

[Bob Kontak]

I will get the pic up here asap - pretty straight forward

[Bob Kontak]

The Cannell sight can balk if you don't have a 5Mbps line or greater.

Here is the pic. Right click and save to your desktop. If not clear PM me your e-mail and I will send. The pic is "clear" on my end before posting here.

Focus on the wires between the switches first. Hot is red/blu and you know you have power so checking upstream of first switch is not where I would go first.



Edit - It is compressed a lot when posting to forum. I can e-mail if you wish.

[1988coupe911]

Thank you so much, Rob. I just printed the diagram and am off to begin...though fear this may be more of a weekend project with my limited experience with electronics...wish me luck! Seriously though, I'll be back in touch and let you know how it goes. Thanks again for your help. -Adam

[1988coupe911]

Sorry, I meant Bob, not Rob. Evidently reading is not my strong suit either.

[Bob Kontak]

Just post questions as you go. There are plenty that know way more than I do.

#1 - Make sure the wire colors match the terminal numbers.

[1988coupe911]

Thanks to the wiring diagram, I realized that I improperly re-wired the passenger window switch on the drivers side when i re-installed it. That solved the blown fuse issue. The weekend project will be the continuity testing.....will keep you posted, thanks again!

[Bob Kontak]

Good deal. Take your time.

New step #1 Make sure connections on the passenger side switch are nice and clean if you have not done this.

[1988coupe911]

Bob, still working on it, slow going but am going to get through it! Thanks again and will keep u posted.

[Bob Kontak]

Originally Posted by 1988coupe911

slow going

That is a very good speed rate for us electrical noobs.

[1988coupe911]

Bob, I finally conceded and took the car in...turns out it was the window motor. A new motor and a couple hours of labor later, and both windows work like a champ. Not the best end to a story on a technical "do it yourself" type forum, but it's at least fixed and didn't cost me a month's pay. Appreciate the help and your time.
Thanks again!