hotshot79

passenger side power window in the 79 stays up, I can see the guage needle move when I move the switch so I believe it's getting power and the driver side works. Is the first step to remove side panel and check the actual switch,wiring, before taking of the door panel and going after the motor? Maybe switch wiring to the working side to see if switch is bad? It stuck in the down position a couple months ago but after playing with the switch I got it to go up, today it won't go down, any thoughts. thanks

pbcanney

i think your diagnosis has answered it.

sounds like a bad switch

they're not too expensive

...Roger...

If your seeing the voltmeter move when you push the switch to make the window go down then the switch is working and the current is finding its way to the motor. These motors have a habit of not moving if the mechanism is in a small bind...like the motor being all the way up and the window regulator has wound up due to a broken lower bracket,rivet,bolt,loose tracks or an inner door panel that is starting to flex and not hold the whole assembly ridged. Sometimes you can bang on the door panel with your fist (not too hard) and get the motor to relax and unbind the window by slowly rotating backwards.This will work if you never put the window up fully again. The best way is to go inside and see whats broken or flexing. Oh and the motor can just be bad also.

hotshot79

thanks for the quick response. I do see the voltmeter move a bit so your idea of a binding problem is probably right on. while the driver side works it goes down so fast I have learned to feather the switch to let it down. sounds like both door panels are coming off for inspection.

79L48

Your drivers side goes down so fast because the coil spring is broken or missing. Your passenger side is likely not moving because of the mechanism as discussed.
I have had a lot of luck taking off the panel and making sure everything it attached as it should be, lubricating the heck out of everything and then carefully helping manipulate the window mechanism while switching the window down.
I say carefully, because of the number of ways you can break something or loose a finger. Last count there were 800 people on this forum alone who lost a digit, or knows someone who did while working in their doors
I use PB blaster as the lubricant because it sticks really well and is non-flammable and long lasting. Dry silicone or graphite may work well, too. This is not a job for WD 40, however.
Good luck!