Quote Originally Posted by sharptonn View Post
GM trucks had a dome light defeat button next to the headlamp switch for a long time. Not certain if they still do.
In these days of body modules controlling the interior lamps and what with security systems and such, cutting a wire and adding a toggle may cause side effects with door locks, etc. It may even set codes in the body module.
Those Ford truck forum guys probably have sorted it out....
For example, my Dodge will kill any lights left on after a while to save battery. You cannot leave the 4 ways flashing at night with truck/trailer parked out by the road while you grab a bite.
Damn BCM shuts them down after a bit.
With the Ford it turns on not only the interior lights but cargo, parking, even the license plate lights. With the computers they can not handle the battery drain of days of old. I have a rechargeable flashlight mounted in my truck and I can't leave it plugged in overnight even if the flashlight is charged or I get low voltage warnings in the morning.

Another pet peeve is that I can't leave the door open and play the radio unless the truck is running......