REMOVING THE 1992 (+/-) BMW 525 DOOR PANEL & Window Motor
If you are sure you don't have an electrical problem, like a fuse, then here's what you need to do:
1) Remove the door panel. by first removing these items:
-- Speaker cover (leave the mirror screw)
-- Screw behind the cover plate...behind the door handle
--- Torx screw behind the cover plate in the upper part of the door handle (This is a long screw)
-- Chrome trim across the top of the door. Just pry it up.
-- Any screws you may or may not have along the bottom of the door
-- Other misc. electrical from the switches (I can't remember all of them) just look.
...And when you are ready pry the door cover...pull it out & push it up from the bottom. There is a semi-hard lip that hooks along the window trim.
Note: You may have to hot glue or use silicon glue to put the door panel back in place, and on my door someone put 4 screws along the bottom for extra hold. It looks good.
-- Remove the foam cover carefully.
-- Try testing the window for power or apply power directly. It's a dc motor so by reversing + & - you will be able to move the window up or down. BTW, you will need the window raised about 1/2 way up to remove the 4 or 5 bolts that hold the window mechanism in place. Or at least you hope there will be bolts . I've heard that some are riveted on and you have to grind these off, and then replace them with bolts. Anyway, you can't remove the window motor without first removing the window mechanism.
Note: Leave the 2 window sliders. Instead, just pull off the retaining clips off, and use force to pop-out the knuckle/pin in the arm... which is pressed into the Teflon slider. (Be sure to order 2 of these window sliders along with your door motor before you start your job. I ordered my motor from BMA for $95.
Also, you can not rebuild the motor. It's got a worm gear that mates with a nylon wheel and there is nothing you can do but buy a new one.
Good luck. It's not hard, but the first time is always a joy!