power windows and sunroof not working, blowing fuses

[Christien]

Out of the blue, both windows and roof are inop. No noise, no nothing. Fuse was blown, so I swapped it, tried it again, and it blew immediately with no movement from the windows whatsoever. There is juice at both poles of the fuse. What's the next thing to check?

[Flat6pac]

separate the wires below the fuse and see if the sunroof is the culprit or the windows are by installing only one.
I had the problem with my 76 and it turned out to be the rear window wiper in the same fuse.
Bruce

[86 911 Targa]

Originally Posted by Flat6pac

separate the wires below the fuse and see if the sunroof is the culprit or the windows are by installing only one.
I had the problem with my 76 and it turned out to be the rear window wiper in the same fuse.
Bruce

Good call!

[porschenut]

Yep, there's a short somewhere on that circuit. You may have a loose connection which finally found a path to ground.

[Christien]

The sunroof cables were recently fixed at a shop. Would inside the headliner be a logical first place to look for a short? I'll separate the wires under the fuse to check first, but assuming it's the sunroof, should I look in there?

[porschenut]

Yes, that's where the problem is, most likely. That's where the motor and drive gear are, and they would have had that area open to work on the cables. Check the wiring at the motor.

[rnln]

You said "tried it again". Try what? What was the action that you tried?

Here was my problem. It was the wire inside the door jam running from under dash to inside the door. When the door moved, even just slightly, the wire came in contact with the hole on the door, grommet was loose and came out of place.

What I tested was leaving both door open, replace the fuse, reach hand in to open window each window without moving the door at all. Everything works fine. Soon I move the door, the fuse burns.

What I did for repair was remove the door, shrink wrap the cracked wire several layers, wrap it again with electrical tape, slip the grommet in place, very tight.

Originally Posted by Christien

Out of the blue, both windows and roof are inop. No noise, no nothing. Fuse was blown, so I swapped it, tried it again, and it blew immediately with no movement from the windows whatsoever. There is juice at both poles of the fuse. What's the next thing to check?

[dshepp806]

People should closely check that wire bundle running through the door,..as it get's flexed over time, allowing the wires to have their jacket compromised and possibly touching ground.

Best,

Doyle

[bigel]

+1 on the wire bundle running through the door jam. I had the driver's side bundle become compromised (some wires completely sheared off) on my wife's DD, '06 Jetta, and the car completely lost power to everything controlled by the driver's door (gas door, trunk, windows, remote door lock/alarm).

With all of the door stop issues out there the door wire harness can take quite a beating.

By the by, I've never had the need to address that harness on my 911, but it looks as though the door would require removal to allow access. Can anyone knowledgeable on the subject confirm?

[ben parrish]

Yes, door removal is necessary.

[Christien]

Ok, I'll check out the door and inside the headliner after work today.

When I "tried again", I tried the window switch. I can't say I remember exactly if I opened the door or not, but suffice it to say that I can't count that out as a possibility.

[Christien]

Ok, got inside the headliner and all looks fine. I disconnected the sunroof motor (white nylOn 2-prong plug), replaced the fuse, then turned the key to the last position before start. I immediately heard the telltale pop of a fuse blowing, and sure enough, it had. Can I thus eliminate the sunroof as being the source of the problem?

[80-911SC]

sounds like it .. no move to checking your rear wiper ... i would use an electrical tester instead of the fuse pop method of testing ..

Use long extension lead and set the scale for ohms and see what you are getting end to end one wire at a time .. also check them against ground and see if they are grounded when they are not supposed to be ...

[rnln]

funny that I, and no one else too, was asking which fuse? :lol:

[Christien]

Should've mentioned, no rear wiper. #1 fuse, the standard one for windows and sunroof.

Talked to the guy at the shop, he suggested taking out the door switches and testing those. Just got back from the store, picked up a box of 25 amp fuses

The wires through the door jamb look ok. Took a pic but it's on my phone - I'll post it when I get a chance.

[Christien]

I removed and disconnected all 3 window switches and it's still blowing the fuse. So not the sunroof connection, not the window switches, wire through the door jamb looks fine, where else now?

[Christien]

Spent another hour poking around today. Still stumped.