I hope this is a 'duh' fix, but here it is:

Top left tail light on truck stays on when engine off and key removed. When truck is on all four tail lights, head lights and front turn lights stay on -- no changes when blinkers on or hazards on, no change with brakes being applied except that third light on cab lights -- also reverse lights work. Ideas?!

 

Look towards trailer wiring being corroded or shorted somewhere, or the TIPM. The TIPM's have been known to fail on the 3rd gens.

 

I'll check the trailer wiring... what is the TIPM?

 

You can't check the TIPM as far as I know. Mine acted wierd & it was the multifunction switch in the steering column. HTH

 

Wellllll funny thing is, I unhooked the batteries for an hour and the problem is currently gone. Guess I'll just have to watch it.

 

THAT sure sounds like a TIPM issue. Now.....what caused the TIPM to freak out will take a little to determine. Check for body codes if it happens again. To do that, hold the trip reset button while turning the key on. The guages will freak out and do a little dance, then any body codes will show in the odometer screen. You can compare the body codes to this chart.

 

page could not be found. Do you have another link?

 

Sorry about that rip! Look at post #5 after you retry the link!