How do i fix the back drivers side electric window in my 1994 jeep grand cherokee limited? it goes down but not up no matter whether i use the switch on the drivers door or its door?

first is diagnosis.
you examine and test it. to see if its electrical or mech. failure.
and once discovered that follow that to logical conclusions.

The main switch as power goes through it first then to the other switches.

The motor is bad. It goes down because the window weight is offset by gravity. It takes much more power to push it up.

it realy matters if v8 or 6. a v8 is about 30 inches wide, has an aluminum top that is similar to a barell sliced in half longwise [alum color of course] laying cut side down. a 6 [assume U.S.] is rather narrow at the top and has a sheet metal valve cover that is black, also there will be a black rubber pipe,about 6 inches in diameter that goes from engine to the left[drivers view] fender.

You would have to take the door panel off to take the window motor off, then run jumper wires to the window motor terminals. If the motor doesn't turn, time to get a new one. But more than likely, if all the windows don't work, it may possibly be a fuse. Also, you might want to check the window switches, they do burn out. I have had to replace a couple on my 1993 Jeep Grand Cherokee.

sounds like you have broken wire(s)between driver's door and post..if you are missing a power or ground feed to master switch,other side will not function as well

Have you tried spraying silicone on both side tracks? Otherwise, the window motor may just be going away.

most of the time it is wires in the drivers door that break in the loom

You might have a faulty switch in the master!! Sounds like the lock and unloc has gone bad on you!!