I came across a problem with my dome light. When it is switched to the door setting, to doesn't come on when the doors open. It works in the ON position, so the ground for that must be working, and it is receiving power. Maybe a faulty ground for the door setting? I don't have a clue where the ground for the door setting is.
any help would be much appreciated, thanks!

 

It should ground through the door switch in the door sill. Switch is probably bad.

 

Do you possibly know what color wire it is?
Thanks for the reply by the way.