2011 dome lights wont come on

First post: I have a 2011 Express 3500. The dome lights wont come on when doors are opened. The dome switch is not pushed in to override the lights. They will turn on/off and fade manually. I have looked for a door jamb switch that may be stuck or faulty, but cannot find one anywhere on any of the doors. I cannot find anything in the manual that addresses my problem. I'm getting tired of the dark.:uhoh:

Were they working before?