2003 Ford Ranger interior light

Try this cure, buy a can of brakekleen and a can of spray white lithium grease, spray the latch area, thats the claw in the door where it closes, spray liberally with brakleen, open and close the door 5-6 times, repeat, then spray with the white lube, open and close the door 5-6 times. Reapeat on all doors.
If this doesnt work, the switch inside the claw will need replacing.