I need your help yall. My 99 Xj has power everything. Just the other day my driver window didn't wanna go down, the out of no where it started working again. It's acting up again tho and now it'll only go up or down if I bang on the door panel a few times. Everything else works fine from the driver door (passenger window, back Windows, locks etc) only my driver window doesn't wanna work unless I punch the door panel lime I said. Any ideas what it could be? I haven't had a chance to take anything apart and look yet I will this weekend but I'd like to know where to look first

 

I had the same issue and these are the two things I did to fix it.
1. Take off the kick panel on the driver side and you'll see 3 wiring looms. The closet to the door has black, light-brown, and yellow wires. Cut the yellow and light brown wires then splice them together. It may not be the fix you need, but it's a common place to start with 97-01 windows.
2. Get a new wiring loom for the door itself and put that in. The wires tend to get kinked and break inside the insulation so it appears all is good when it's really not.

It's not a real tough job, took me maybe 90 minute total to do both steps.

 

Same issue in my ZJ.. kinked wires in the door. ripped off rubber grommet deal, re-connected wires, good to go