This appears to happen when the motor gets jammed at the very end of the rack. If you hold the switch down after the window reaches the top you can actually see the inside of the door flex because of the stress.

I have had this happen a few times. Sometimes it frees itself up after awhile (weather conditions, perhaps?). When it doesn't, I have removed the inside panel, removed the nuts from the lower bolts that hold the regulator in place, and them gently knocked one of the bolts out with a hammer (the stress on the regulator arms will put a lot of friction on the threads). Removing one bolt should relieve enough stress on the assembly to turn the motor and crank the rack back a bit. Then you can bolt it back in and it should work.

Oh, yeah, remember to duct-tape the window to the seals first so that it doesn't fall down when you loosen the regulator.

Jim Wiggin
Columbus, OH
1989 300E

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Jim Wiggin
Columbus, OH
1989 300E