Door ajar light staying on

[linkysys]

Wanted to post this to help anyone troubleshoot a similar issue. My 03 Explorer had the door ajar light staying on constantly. I tried spray silicone on all of the car locking mechanisms. I did notice that slamming the driver door sometimes caused the light to shut off. I found this excellent video on Youtube with troubleshooting steps-- . I pulled the harness off of the lock sensor switch and jumpered it with a paperclip. The dome light functioned as expected when jumpering the pins. I tried jiggling the wiring harness in the door jamb with the pins jumpered to test for shorted wires. The dome light continued to function correctly. I determined that I had a bad door lock sensor switch. Access is very difficult. You will need to reach into the door and remove the clips that hold the pull rods to the lock and pull the lock into an area of the door with enough access to remove the sensor. I used a 90 degree pick tool to help remove the clips. I found a lot of resistance trying to rotate the sensor clockwise for removal. There is a plastic retaining clip integrated into the door lock that holds the pin on the sensor. I struggled to remove the switch and access was difficult. On my car, they had wrapped the switch with tape that I had difficulty reaching with my hands to remove. I wound up using locking pliers to rotate it off. In the process, I broke the plastic retaining clip that is integrated into the lock. Why they didn't simply make the entire lock out of mental is beyond me. Consequently, the replacement lock sensor would not stay in place. This forced me to also order a new lock. I went with generic parts off of Amazon for cost savings as the Motorcraft parts were triple the cost. If you are doing this, I suggest ordering both a new lock and the sensor just in case you damage the slotted plastic retaining clip. There may be a way to release the lock sensor retaining clip for removal but it is not described in the video. Note that the plastic rod clips and bushings are sold separately so you will need to transfer them from the old lock to the new lock. Also note that you will need to slide the black plastic actuator off of the lock in order to transfer to the new lock. There's a retaining clip that you need to depress with a screw driver to slide off the actuator. You can find videos on it as well. The rod clips on the lock can be brittle so you may need them as well.

One day after this repair I had my brake sensor switch fail on the same car. I suspect these switches have a design life of about 20 years.

 

[Stynx]

Yeah after 20 years it doesn't owe you anything. All those old hoses, gaskets, fittings, connectors are all deteriorating with age and heat stress. I am grateful ours runs reasonably well.