2000 grand prix gt Interior lamps problem

[rainlake]

all the interior lamps did not work. I checked fuse
"INT LAMP Mall Module -- Interior lamps", it's OK.
I checked the voltage at this fuse. it's 12V.
any suggestions? thanks

 

[Pepino]

but maybe a bad "door switch". The one that lets the car know a door is open?

 

[rainlake]

will the bad "door switch" cause all lamps stop working? even I turn on the map light with push the "on"button ?
thank you.

but maybe a bad "door switch". The one that lets the car know a door is open?

 

[supercharged06]

Doubt it cause the door switch isn't tied in as part of that circuit