Just to clarify the truck is a 2006 GMC
3500 with a duramax 6.6 and Alison 6sp auto.
have checked fuses several times. There is no power to the orange wire at the brake switch from the
stop lamp fuse under hood. This truck has a tow button on gear leaver that is not working also.
I think there is a cruise mod. under the dash that may control all of these things.
Also is there a web site I con go to for a wiring diagram of just this truck.