I cannot figure out my '00 XJ rear defroster issue so I really hope you guys can help me out. When the switch is pressed, both the light and the defroster (both mirrors and back hatch) fail to turn on. The fuse, relay, and hatch wiring are all good. I assumed replacing the switch was the only thing left to do, but that has not fixed my issue.

I am leaning towards a wiring issue up front but I cannot find enough information to test if that is the case. Does anyone know what my next step might be?

Thanks

 

You checked the hatch wiring, but did you check the back window itself to make sure the solder hasnt come undone from the window? Also, check the grid for any breaks. If both are good, its back to the wiring.

 

Solder is intact and the grid is fine. I believe the switch would still light up if the issue was only in the hatch.

 

After a couple years of on and off troubleshooting this problem, I finally learned how to read wiring diagrams enough to find the problem. Apparently there is a 30 amp fuse 11 in the power distribution center and it was cooked. Its only purpose is to feed power for fuse 13 (spare) and terminal 30 of the defroster relay in the fuse box. Fuse 14 (rear+mirror defroster) only receives power when the relay is functioning properly.

Since the 10 amp rear defroster fuse was good and the spare fuse is empty, I didn't think to check for another fuse up the line. I have no clue how the 30 amp failed.