Originally Posted by NIT2WN
Not exactly sure on the F250, I've had the interior light problem off and on in my 03 F150 and just sprayed some WD40 in where the latch is on the door. It usually goes back to working. I don't drive it much is my problem.
Same for the superduty. Just get some WD40 and open the door. Give it a couple of good shots in the door lock mechanism on the door edge. Open/close the door, work the handle, give it a few more shots in the mechanism and work it again. It should all be back to normal for you..