It is more then likely in the door switch. I have an 2000 F250 and am having the same problem from time to time. The dang switch is located inside the door, not like the good old days where you could see the switch. There is a piece of metal about 1/4 up from the bottom that if you look slides into the door when closing. I haven't fixed mine yet but was glad to read about the fuse if it happens again at night.... Guess I will have to take it in if I don't sell it first.
Steve | 
