Ok I have the same issue in two XJ's a 91 and a 95. The headlights work but the marker and dash lights don't. Tried two different switches, no luck. Grounding? relay?

If anyone can help it would be great.

are the marker lights and turn signals in the same light? if the turn signals work and are in the same light its not a ground problem.

I haven't seen this in a Jeep but I have seen this issue in other vehicles and it turned out to be in the ignition switch on one of them so this may be a place to look.

THe first thing to do is to check all fuses. Then use a test light and see if you have power and ground at the light. Chances are you will have one but not the other. and just work your way back untill you find the problem. It could also be a light bulb that is shorted out. To find this unplug the bulbs one at a time untill you have found the problem or been through all the bulbs.

Thank you everyone we will try your suggestions.

You beat me to it. I just had a 01 Chevy Tracker in today. I had to do some digging in the fuse box and sure enough the marker lights and dash lights were on a dedicated fuse all by themselves. That is the first palce I would check.

Thanks evryone! 95 Lights fixed waiting to hear back on the 91. It was a bad bulb and a blown fuse. Such an easy soultion over looked. Hope to help someone else someday.

Thank you