Originally Posted by heydave
I would say that you have a broken wire in the doorjamb. I have read that you can disconnect the wire harness from the door and unplug from under the dash to remove for repair.
Not on the '96+ ZJ's - the harness that runs to the doors is part of the floor wiring harness. It could be unplugged and pulled back to do the repair, but it would have to be done in the vehicle. Pulling the entire wiring harness is pretty involved - the seats need to be pulled, the kickpanel trim, rear side panels and carpet have to come out too. Those rubber boots at the front doors are a PITA too - especially the passenger side.
If there is a broken wire in the door jamb, the proper way to repair it is to remove the section that is in the rubber boot and to have the solder joints near the plug and outside the boot. If it's fixed in the area where it repeatedly bends, it will fail again.