A conundrum... I have purchased a '98 Ranger w/ 4 liter V6. I can't seem to be able to figure out the Door Ajar system. Which, of course, controls the overhead dome lights. Most of the time the Door Ajar light stays on for the entire trip and also the dome light which will stay on after I park and turn off the key. Occasionally a few minutes to an hour into a trip the buzzer will sound twice and the Door Ajar light and the dome light will go out. Very rarely, the Door Ajar light will go out after backing up and putting the truck in drive. Because of this situation I have disconnected the dome light to ensure that I don't drain the battery. I sure would like to fix this issue, which is the last item on what was a short list of fixes with this purchase. Anyone have a suggestion?

 

Spray some WD-40 into the door latches

 

Sounds bad connection or shorted wire to me. See if wd-40 works and update us..