I have a 2000 XJ8L, - having issues with license plate lights, I got pulled over the other day (the finest Police), and ONLY my license plate lights were not working, I have replaced the bulbs with exact replacements. I went through all of the fuses and all of them look good. The only thing I can think about that would cause them not to work, is that my rear view mirror about 5 months ago leaked black stickey stuff, now it is fuzzy and no longer a good rear view mirror.

 

Check the wiring loom that runs along the Right Hand Boot (Trunk) Hinge. Chances are the wiring has snapped here and you will need to repair it. It is a common problem with these cars sadly. Hope This Helps. S.

 

Stu: I've had similar problems with trunk lighting, and have read about the harness on numerous posts. Gave it a quick look and nothing jumped out at me. My stupid question of the day is....does the insulation also normally break so you can clearly see the problem, or is it just the conductor still hidden from view? Thanks.

 

Re. licence plate lamps -- if they are the kind where the lead-out wires from the lamp/glass bulb are just plain metal (no cap) you can get corrosion between the lamp and contacts in the holder. A check is easy -- while lamps are switched on, push the lamp in and out a few times to see if you get any flicker. No flicker, look elesewhere. If nothing else shows up, remove the lampholder and examine carefully for bad wires and corrosion away from the actual connectors to lamp/bulb. The boot/trunk on many cars runs quite damp in winter weather, and corrosion is easily possible.
Leedsman.

 

This is the Origional poster... I checked the wiring loom (right trunk hinge, tried to move it and it does not flicker any lights at all... It seems to be as sturdy as if it was brand new.

I can move the insulation easily and expose all of the wires... all looks good (will need to better inspect (along with the loom above)

 

You will have to get a tester and see if you have power in the wire to the lights and trace it back -- if you can not find a problem with the insulation.

If your reverse lights failed - that would be interesting -- most of the mirrors have an interconnect to the rear lights to turn the dimming off when you are backing up.

Not sure how the mirror could do anything to the license light.

 

I'm with Leedsman. Test for voltage directly at the Bulb connections. That would be the easiest test before tearing the wiring loom apart. Pull the bulb out, then connect a tester there. If no voltage, test backwards. You can insert a straight pin into the wiring insulation to make a connection for the tester along the route.