I was trying to get the power windows working on my '89 GL 3-door coupe. I found a bad ground on the passenger's side, got the pass side switch working by 'adding' a ground, and then was having trouble with the pass window from the driver's side.
In the meantime, I 'ordered' a new switch on eBay, just in case...
I took the driver's door control out, opened it up and cleaned the contacts (some of them were carboned heavily), put it back together and the pass window went down OK, but up hard (um, with some smoke coming from my whopping 22GA 'ground' wire...
Took it apart again, cleaned some more, and tried again. Up and down OK, more smoke from the ground.
Removed the ground and the pass door was working. The third time I took the switch apart, I lost one of the little rollers on the pass side switch. OK, there's two of them, let's see what happens...
Cleaned everything again and put it back together, and both windows began working perfectly. Except...
With the roller missing, the pass side window is now auto up/down. It does this by the switch sticking in the related position. This is what I was going to try to attempt to do with the new switch.
I also found the Lock button works on either switch, so once the window is where I want, I can 'Lock' the windows and be safe. I believe the Lock button interrupts the ground so no current can flow. I believe this was the original trouble with the pass window.
Now to find some speakers that work...(who the heel designs the rear so you have to remove the WHOLE REAR INTERIOR to replace the rear speakers?!?!? um, Subaru, and whomever designed the 86-92 Supra!!!)