I have a problem I can't figure out... if you have either Rt or Lt blinkers on they will stop blinking if you step on the brake. also if you have the cruse control on it will drop if you turn on the blinker.
Anybody know where to start?? possible column short??

 

well.......if the 03 is any thing like the 97 the brake lights turn signals and flashers all go through the multi function switch in the column....but that being said this system is complicated it could be the brake light switch also its real hard to say for sure but those are the 2 places I would start looking.........use a test light and start at the turn signal switch and keep testing untill they stop flashing but again this system does alot of handling of many systems

 

Welcome to the forum. Have you done anything to trailer lite socket/wiring or connected a trailer recently?

 

No changes... we've done nothing other than drive it.

 

Sounds like a wiring issue like an open ground and a circuit being back fed. A real PITA to troubleshoot.