Car Wiring Diagrams for Horn circuit for GMC Cab & Chassis Sierra 3500 (2004-2007)

BLK WIRE BLK/YEL WIRE BODY CONTROL MODULE (BEHIND LOWER LEFT SIDE OF DASH) HORN RELAY CONTROL DK GRN WIRE HORN CONTACT HORN FUSE HORN RELAY HOT AT ALL TIMES LEFT HORN (LEFT SIDE OF RADIATOR SUPPORT) NCA WIRE RIGHT HORN (RIGHT SIDE OF RADIATOR SUPPORT) TURN SIGNAL CANCEL CAM TURN SIGNAL/ MULTIFUNCTION SWITCH UNDERHOOD FUSE BLOCK (ON LEFT SIDE OF ENGINE COMPARTMENT)