I just noticed this yesterday, guess I never really look on that side...I opened the passenger door and noticed it wasn't lighting up so I though ok maybe its the bulb. So I took the bulb out and its fine so I swap it with the bulb from the driver side door. Still doesn't light up, checked all the fuses they're fine, so I put the bulb back in and think ok maybe its loose, so I push it in a lil more still nothing, I even moved it around a lil still nothing...

 

Check the black rubber looking plunger on the side of the door frame. That's what turns on the light when you open the door. It might be stuck or may have come unplugged.