On my 2002 F-350 I had a variety of symptoms. Door ajar light staying on, Radio staying on, loss of auto headlamp feature, dome light would only turn on manually.. I hoped and prayed it was just a stuck door stitch of course it was not.
It is the VSM module, Vehicle Security Module which is located behind the cupholder'radio area. its about a buck fifty, thats the good news. The stealership will charge a hour labor to tell you what I just told you and another hour to reprogram it.. At least they fixed problem this time!! I have seen other posts with exact same symptoms and after these guys chased door switches still had problem as I did.
What I share here is only my experience.
