The door ajar switch on the 2008 Ford Sport is located inside the door that is mounted on the backside.
add a couple layers of tape where the switch hits the door jamb. the tip of the switch is worn down.
Just to the right of your headlight switch is a gauge lighting dimmer wheel switch , if that has been rotated all the way up it turns on your courtesy lights when the doors are closed. Also , if a door ajar light is on in your gauge cluster you probably have a sticking door ajar switch
I had the same problem with my 02 Ford Ranger the sensor is inside the door (genius idea ford). no amount of wd40 helped. luckily for me it was my passenger door. I just unplugged it and the dome light doesn't turn on for the passenger door but works find for the driver's door.
Try spraying WD-40 on the door latch, the part that is on the door itself. The door ajar switch is located in with the latch. Had the same problem, door ajar light on, interior light stays on, and horns toots twice when you lock with remote, to signal door is not closed. Door was shut but truck didn't know it, WD40 fixed it.
The door ajar switches are inside the doors mounted on the backside of the latching mechanism - They have a pin switch which tends to get dirty causing them to stick so the door ajar light comes on in your dash. Some fellows spray the latch mechanism with WD 40 but I think an electrical contact cleaner would work better - Helpfull
Just to the right of your headlight switch on your dash , is a gauge lighting dimmer wheel switch . Check to see if that has been rotated all the way up. If it has , that turns on the courtesy lights when the doors are closed If you also get a door ajar warning light in your gauge cluster , you probably have a sticking door ajar switch . The door ajar switches are inside the doors , on the backside of the latching mechanism .
Pull the door panel off, remove the door latch assembly from inside the door, and replace the switch which is hold onto the latch with one screw on the backside of the latch.
Blast the switch with some wd40 and push it in and out a bunch of times, this usually works on fords when the light wont come on but its worth a shot. If no luck you will have to replace the switch.
Inside the door , mounted on the back side of the latching mechanism
It has two. One behind the drivers side door panel and one behind the passengers side door panel. I just purchased one for my 2000 Ranger for $10 at my local parts store.
The door ajar switch is part of the latch, inside the door.