Rear Windows won't roll down

[Eno]

I tried searching on here before posting this but my phone wont work with the search function on here so sorry if this has been answered already.

I dont know anything about how to diagnose these and i searched but always seem to find ppl working on the front driver side. They are stuck all the way up (Thank god for that at least) but when i try to roll them down i just hear like a buzzing noise like its trying to do it but whatever it is keeps it from going down. Would that be the regulator or motor? Or how can i diagnose this? Thanks in advance.

[sonikaccord]

The best way to diagnose this is to get your hands dirty.
Take off the door panel, remove the regulator and test it by applying battery power directly to the motor. Observe what happens. If anything looks weird, you can replace it. Or at this point, you could replace it anyway since the panel is off.

Check your window run channel for deformation, debris, sticky stuff (ewww), or lack of lubrication.

[StevenCrowtown]

from working at LKQ almost 2 years you see all kinds of crazy stuff. Try 3 Cadillac CTS's with rear regulators that were junk and someone jammed the window up with a piece of 2x4 or screwed a wooden block under the window all the way up. Get that door panel off and see what you're working with.

[F22Chris]

I bet it's the rear motors if the front two roll down. Window switches share a common ground, so if the front work, that's fine.

Put 12v to the rear motors and see if it works. If not, R&R.

[Eno]

I bet it's the rear motors if the front two roll down. Window switches share a common ground, so if the front work, that's fine.

Put 12v to the rear motors and see if it works. If not, R&R.

Thanks. Ill go ahead and get those off my next day off and see what i see.