GMC Repair: Dome light `door switch, latch assembly, door switch

Question
I have a 2001 GMC 2500 Sierra with a problem with the dome light not coming on with the Passenger door opened. Question I have is to where is the door switch located at and is that the problem?
Thank You

Answer
Hi
The switch is actually part of the latch assembly, which is the part in the door.
I have replaced a few of these for similar concerns.
Is it your problem???? I cannot tell you.
It COULD also be wiring or the Body Control Module. The BCM controls the relay.
I Hope this helps.
Good luck
Pawl