I have seen similar questions but none of their solutions have worked. I have a 1994 Jeep Cherokee Country 4d and my tail lights/parking lights as well as my instrument panel lights are out. Here is some other relevant info
the brake lights still work
the turn signals still work
the bulbs all work
fuse wise I have looked at the fuse page in my manual and checked every fuse that even remotely mentions something related to the IP lights but nothing references the tail lights or parking lights. I might not know the lingo but I can post a copy of the page if need be

Please help

 

Welcome to the forum.
So, "none of their solutions have worked" : what things have you tried yet?

My first go would be to go out and spend some time on:
1) checking all fuses
2) cleaning up all ground connections
3) checking connections

Simple/basic stuff first.

 

I think the gauge and consul, (shifter), share a fuse with the tale-lights. I wonder if 94 has a fuse panel up under the dash, as well as in the PDC under the hood. It might be way over on the left.

 

check fuse 15 under driver side dash

don't just look at it, test it.
also see if you have voltage across that socket

 

Mine did that . I found a wiring harness had shorted out under the air box

 

I know this is a really old thread, but I came here because I had the same exact problem and same year jeep xj (1994). No running lights, and no tail lights when the headlights are on. If you haven't already swapped out the headlamp switch, do that. After 2 months of trying to find out this problem myself, and 2 different professional mechanics $$ who were stumped and gave up, I found the problem. The cargo light housing had a short in it. I removed it from the vehicle, unplugged the whole thing.