Not your usual dash light problem.....
 

I bought a 98 xj for 875, replaced the motor after discovering it was blown, drove it for about 1000 miles then installed a new headunit. I went to the store with the lights on came back out turned the lights on and to my surprise the headlights worked but the dash and center console lights did not. I changed the light switch and check the fuses, which are the popular culprits and they still don't work. I also tried to read some codes I was throwing and there was no power at the obd port.
Now I'm stumped any suggestions??

where does the power at the 5 amp fuse come from?

I pretty sure you shorted the circuit. The fuse it in the pdc under the Hood it a 15amp fuse it controls the dome lights and dash. But so does the the 5amp in the kick panel. Here is the link from lund.

http://www.lunghd.com/Tech_Articles/...tification.htm

You probably know this but just in case the headlight knob turns to dim or brighten interior lights.

both fuses are good and if i jumper from a constant to the gauge light wire (where the switch plugs in) the dash lights work....maybe a defective switch?

About when did you install the headunit? And everything worked fine before the install and after? When went to the store everything still working, did your thing and lights worked but dash light right? Radio working fine? Could to tell if everything else in the cluster was working?

It's possible too that you might have pinched one of the wires when attaching the lower panel but that would of blown a fuse. But if 12v is applied everything works like it did. Try swapping switches over and look at wiring to see if anything nicked too.

I have a good 12v constant coming into the switch and if i jumper it to the dimmer pin all the dash lights are functional I had to of gotten a defective switch

It has to be you could do a continuity test but it's easier just to swap a new one or even the old one if both do the same then it another problem but if it fixes it then you'll know for sure

I have tried 3 switches all brand new all act the sameway... If i move the plunger just right the running lights will come on but if i pull it out to have the headlights on i have no running lights

Did you do any work on speakers in rear hatch?

nope.... I am gonna go replace all the bus fuses in the power distribution block because this xj was just having the same problem
http://www.naxja.org/forum/showthread.php?t=1022965

Checkng for power on both sides of fuses should be checked with key in run position.. if theres no power replacing fuses wont help.