I have an 01 xj I’ve been slowly fixing up. One problem that’s stuck around and annoyed me is the rear defroster light will come on around 50% of the time the car starts. I’m unable to turn it off until 20ish minutes of the light being on. The defroster still functions normally but it’s a problem I want to fix. Any ideas?

 

Does the defroster also come on or is it just the light on the switch? Either way, check the switch.

https://www.rockauto.com/en/catalog/...er+switch,4336

 

Anything on the liftgate I'd immediately suspect the wiring in the bellows where it enters at the top.

The 20 minutes might just be the timer function - although I wouldn't expect it to be that long