New problem on my SD, When the window is rolled down all the way it won't go back up. If the stop that presses agains the frame is loosened, then it will go again. Is there some relay somewhere that cuts the power to the motor after it get to the end of the window travel? With the motor out of the frame it will turn forever, there must be some mechanism the tell it to stop trying to turn after the window is fully up or down, is it built into the motor itself, like a circuit breaker that trips once the motor can't turn anymore that is having problems reseting itself?

Maybe something is loose inside?

I'd take off the panel and have a looksee... my fuse caused my window to stop operating.

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That's the frustrating part, took the panel off, pulled the motor, was ready to swap it,but it runs fine off the frame, window slides up and down track fine by hand with motor out, reassemble every thing, works fine, think I have the problem fixed, then it hits the bottom of it's travel and stops again and won't go back up. Take every thing apart again, same story. It's got to be something in whatever makes the motor realize it's hit the end of the window travel....

No, it's up to the driver to let go of the switch. The window can jam, and the motor will try to move the window, but be unable. Check your dome light, see if it dims when the window does not move. If it dims, the motor is drawing 'stalled' current, the maximum it can stand.

Best Regards,
Jim

AFAIK there is no electrical switch that controls the motors. This is definitely true on the up position and I'm fairly certain that it's also true on the down position. This is the reason the regulators are bent all to hell. If you force the window closed, all the motor torque goes into bending the regulator frame.

Take a look at the regulator and see if the gear is missing the last two teeth when the window is all the way down. The motor may run fine, but won't engage the teeth in the regulator if they are stripped. It's a common problem due to the power of the motor and it's ability to wear out the teeth at either end of the travel.

Don't leave your finger on the button after the window reaches the end of it's travel. The regulator will thank you for it.

No, there's something in there, after about 8-10 second of the switch being held while the window is stopped there is a click, the current to the motor is cut, a pause, and then another click and is reset itself. If it's just the finger on the switch, why is it only stopping working when the window get fully down against the stop? After it jams, if the stop is loosened so there a little motion in the window again, it rolls right up.

Is it possible that the regulator is so badly bent, and binding the glass, that the motor does not have the strength to push the glass up from a fully down positon?

Can you remove the motor and see if the glass is free to slide up when everything is bolted up properly?

It sure sounds like a mechanical jam of some kind.

OK, that could be a self-resetting circuit breaker. If you leave the switch on with the motor is stalled and drawing too much current, the breaker trips before it does something drastic like melt or catch fire. The second click would be the thermal element in the breaker re-setting so the motor can again work, without requiring you to remove the door panel to reset it...

In any case, it is not a full-down or full-up switch, it's there to protect the motor from meltdown...

Best Regards,
Jim

Appreciate the input so far, the window is not binding, slides up and down fine with the motor out, it's not stripped teeth as the motor is not spinning after the window stops moving, and if you stop it the tiniest bit before the stop hits the frame, it rolls back up just fine. It's only when the bumper hits the frame that the motor suddenly won't reverse and drive the window back up...

I can't tell if this is your problem or not, but here's my observation. I had a stalled rear side window on my '82 SD. What I found is that the top edge of the rubber-like mat that is glued to the door had come unstuck and interferred with the plastic pawl that pushes the window from the bottom. It would hit the loosened lip and stall while going up; going down was no problem.