The old forum had a good artical on the problem.
The main problem is the worm drive in the motor uses plastic gears.
I removed my roof console and just wiggeled the motor assembly and the motor started working again.
To remove the roof console you have to pry out the dome light/reading assembly with a screw driver. Pry on the rear corners only. When the light assemble pops out you will see two screws. Remove them and slide the console toward the rear of the car.
Tap on the motor with a wrench, there could be a deadspot in the motor. Then wiggel it with your hands.
