Even though no one bothered to reply to my question a week ago, I thought I would come back and help anyone with the same problem as my daughter's 09 Ranger. She has the 4 x 4 with the two little rear doors. All I read here and elsewhere was if you sprayed WD-40 in the door lock, it usually fixed the problem. Well, a can later it did not so I decided to take the thing apart. First I pulled the plug and shorted the two inputs, expecting the light to go out. It did not. So the problem was not the sensor in the door latch. (Thankfully I did not have to go further) For the hell of it I pushed on the little rear door, and lo and behold, the light went out. So there is also a latch sensor in the rear door (bottom latch) , which either no one reported in thee threads I read, or perhaps I missed the thread. Anyway, I sprayed brake cleaner in the bottom latch ((was never fond of WD-40 for anything as it eats rubber) and did the 20 - 30 closing and sure as ShitZ, it worked. So it was not the passenger door, but the rear passenger door. Hope this helps with any one that has the four door model. Just as a side line, and how I bug my daughter about her Ford (I would never drive one) but what engineer in their right mind would put a locking sensor at the bottom of a door, where all the crude accumulates? Very poor engineering.