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-   -   PS window died (https://rennlist.com/forums/928-forum/800673-ps-window-died.html)

j.kenzie@sbcglobal.net 02-17-2014 09:41 AM

PS window died
 
Hi
I lowered both windows 2-3 mm last night, but today the ps side would not go back up. I get no sound of a motor trying to move. The switches are just a couple of years old. Power locks work fine. Window Worked perfectly until today. Any ideas where to start looking?
Thanks,
Dave

WallyP 02-17-2014 10:19 AM

I would try swapping switch plugs first to check the switch, which is the most common failure.

If the switch is good, you get to pull the door panel - lots and lots of WYAIT's hiding in there.

I would check for power on one of the wires going to the motor, with the switch pressed for down then up - one way should put power on the wire. If you get power one way, check for power on the other motor wire with the switch pressed the other way.

If you have power only one way, you have a broken wire. If you have power both ways, the problem is in the motor.

There is a tiny thermal circuit breaker in the end bell of the motor. These sometimes corrode and lose connectivity. Sometimes, you can clean the contacts, sometimes not. I have had to bypass the breaker...

The brushes may be worn, or more likely gunked up. Freeing the brushes might fix the problem.

Good luck!

Wisconsin Joe 02-17-2014 11:19 AM

Wally's checks are very good (as always), but the first thing I would check is if power is being drawn when you hit the switch.

Engine off, key on. Push the switch. If the voltmeter twitches, then the switch is good, power is going to the motor (motor bad or jammed, window jammed, ect). If the voltmeter doesn't move, then power isn't going to the motor (switch, wiring, breaker ect).

Where you look to fix it is very different depending on the results of this.

If your dash voltmeter doesn't work, you can turn the headlights on and see if they dim a bit when you hit the switch.

j.kenzie@sbcglobal.net 02-17-2014 11:36 AM

Thanks
Will check
Dave

j.kenzie@sbcglobal.net 02-17-2014 12:08 PM

Well, my car took pity on me. I went out to it and the window closed first try. We're supposed to get 3-6" of snow today, so I will postpone any manipulations of that window for now. I almost never use it, and it's staying closed to the foreseeable future.
Thanks again,
Dave

M. Requin 02-17-2014 03:17 PM


Originally Posted by j.kenzie@sbcglobal.net (Post 11141683)
Well, my car took pity on me. I went out to it and the window closed first try. We're supposed to get 3-6" of snow today, so I will postpone any manipulations of that window for now. I almost never use it, and it's staying closed to the foreseeable future.
Thanks again,
Dave

Keep Wally's hint about the thermal breaker in mind if you have to dig into it- it's a little hard to discern, just follow the current path, but they do cause trouble. I've bypassed one (replacement motor on the shelf in case) and it fixed the problem. For now.

j.kenzie@sbcglobal.net 02-17-2014 03:18 PM

Thanks, Martin.

DKWalser 02-17-2014 04:11 PM


Originally Posted by WallyP (Post 11141462)
...

There is a tiny thermal circuit breaker in the end bell of the motor. These sometimes corrode and lose connectivity. Sometimes, you can clean the contacts, sometimes not. I have had to bypass the breaker...

What's at risk if the circuit breaker is bypassed? If the worst that can happen is that the motor is burned-out, fine. Likely the motor would have needed replacing had you not bypassed the breaker. But, isn't it possible the breaker is protecting other things in the car?

Glenn M 02-17-2014 06:04 PM

My old Saab 900 used the same motors, I want to say 85-92.

WallyP 02-17-2014 08:22 PM

If the switch jams on while you are driving (or just ignition on), you would probably eventually fry the motor. The fuse should protect the wiring if the motor eventually melts and shorts the power to ground.


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