Currently my ABS and Brake light illuminates after I start the truck and am going down the road. If I just start the truck and let it idle, it doesnt illuminate. I bought a scanner tool and found out the hard way that they dont read ABS codes from the CAB (Antilock Brake Control). Also, my cruise control in INOP but the speedometer works fine as does the overhead computer and the odometer.
After reading this thread, I've decided that its most likely the auxillary brake pedal contacts that feed into the PCM and the CAB. I'll have to get under the dash tomorrow and take a look at that switch.