I know this isn't a Liberty forum, but please help me out with this problem. I have worked with Cherokee's (particularly the '98 model XJ) so I do have a lot of mechanical experience and understanding of how to approach working on a Jeep. I know this is a common problem among liberty's, apparently from what I've read the window just suddenly falls and it will not go up or down (window regulator failure). THIS IS NOT THE CASE FOR THE LIBERTY I AM WORKING ON. Her window will not go up or down period, it is stuck closed, if you operate the switch you can hear the motor humming/buzzing, which tells me the motor is not broken. I keep hearing "the window regulator has failed" but I still don't understand what the window regulator is. Is it what "determines" how far up or down the window goes as you operate the switch? PLEASE HELP!

 

The "regulator" is the assembly that moves the window up and down. The motor is part of that assembly. You might hear the motor humming, but if the assembly is broken the window won't move. It sounds as if you have a broken regulator. It's also possible for the glass to come off the track (the part of the regulator assembly that holds the glass) but generally, if the glass and track separate, the window will just fall down. You won't know for certain what's going on in there until you remove the door panel and look at it. I see a new regulator in your future.

 

I have a friend that has had all four window regulators replaced in her 2007 KJ, some more that once. It is just a plastic part. There are Youtube vids that show it.