My442

My 2008 Grand Cherokee has a strange problem: the right side rear tail light does not illuminate when you turn on the headlights.

The brake light and turn signal both work - just the running light does not work.

Tried new bulbs, did not work

Swapped sockets from side to side, did not work

All 3 other lights work as intended.

All help appreciated.

kjr442

I had to ask my son about this one, he tells me this is a well known problem with the Cherokees. I really do not understand why, but he said just remove and replace the tail light assemble.

MDchanic

It may be a computer-related problem.
I know my 2000 has the computer controlling an unusual variety of things - for instance, when you turn on the signal light, the signal light switch asks the computer to run the signal, and the computer then flashes the lights at the specified frequency, and also makes a "clicker" in the dashboard sound, so you know they're on.
Yours could have the computer involved in turning on the lights, and it may be getting a bad message from somewhere.
Believe it or not, you may find the answer by connecting it to a diagnostic machine (probably a dealer model, though).

- Eric