Just picked up an 2006 ford f250 crew cab with 114,000 miles and all the doors ajar switches aren't working. Any ideas on what could be the issue? Have an 05 f350 crew cab, 06 f250 crew cab, another 06 regular cab and an 07 f250 extended cab in my fleet at work and never encountered this in the last 6 years. Thinking as ive looked under the dash and they had a remote start system on it at one point that i may have messed with something. Just kindda bugging me.

 

Usually when 1 or 2 items aren't working we look at individual items, however, when a whole string of items are not functioning we usually look for power supply or ground problems. I believe there is a ground connection located inside the cab behind the driver's seat in the corner area. It's hard to believe a connection protected inside could be a problem, but should be confirmed good to eliminate that possibility.
In the process of removing the remote start syst they might have opened the power supply to the security module and what that module controls.

 

Ill check the ground there, ill be going though the wiring tomorrow when i get a chance to pull it in. Just odd that it is the only issue I'm having and its on all the doors. Everything else is working as it should.

 

One of the first things I did when I bought my truck (new), was to disable the door ajar switches (disabled by pulling the ignition cylinder and putting a piece of tape on the contacts). I was a hunter years ago and the door chimes were a nuisance. Sets a B1352 code when you disable them, but you need a decent code reader to ready body codes.