Where is the mechanism that controls this? Isn't there usually a little actuator that sticks out, and when the door closes, turns the dome light off?

 

If it is a 96 or newer, the switch is located inside the door on the latch mechanism. Spray some quality lubricant inside the door around the latch and open and shut it a few times. Be sure to do all the doors.

 

can u tell me what cleared your problem?......i have the same problem with my 02 taurus

 

Try spraying the inside of latches and see which door is the problem. If the door is closed and light goes out, that is problem door. You may need to open and close door a few times to get the switch working again. The switch is not expensive but a real PITA to replace.

 

It started intermittent, now most of time, seems to be driver's side door (2002 Taurus SES) Still less than 100,000 miles and other than a fuel tank pressure switch has been a trouper.