GMC Sierra IV (2018-2022) Trailer tow circuit

2.7L TURBO BACKUP ALARM (IF EQUIPPED) BACKUP LAMP RELAY CONTROL BATTERY FUSE BLOCK BLK WIRE BLU WIRE BLU/BRN WIRE BLU/WHT WIRE BODY CONTROL MODULE (LEFT END OF DASH) COMPUTER DATA LINES SYSTEM EXTERIOR LAMPS CIRCUIT GMLAN SERIAL DATA - 1 GRN WIRE GRN/VIO WIRE GRN/WHT WIRE GROUND 17 GRY/BRN WIRE HOT AT ALL TIMES HOT W/ IGNITION MAIN RELAY ENERGIZED LEFT TRAILER STOP/TURN SIGNAL LAMP RELAY LEFT TRAILER TURN SIG LAMP CONTROL LH REAR TRAILER STOP/TURN LAMP CTRL LOW SPEED GMLAN SERIAL DATA NCA WIRE PARK LAMP RELAY CONTROL PARK LAMPS RELAY RED/GRN WIRE RED/VIO WIRE RED/YEL WIRE RH REAR TRAILER STOP/TURN LAMP CTRL RIGHT TRAILER STOP/TURN SIGNAL LAMP RELAY RIGHT TRAILER TURN SIG LAMP CONTROL RUN/CRANK IGNITION 1 VOLTAGE 4 SECONDARY FUSED BATTERY POSITIVE VOLTAGE 56 SECONDARY FUSED BATTERY POSITIVE VOLTAGE 58 STOP LAMP RELAY COIL CONTROL TRAILER BACKUP LAMP CONTROL TRAILER BACKUP LAMPS RELAY TRAILER CONNECTOR TRAILER LIGHTING CONTROL MODULE TRAILER PARK LAMP CONTROL UNDERHOOD FUSE BLOCK VIO/GRN WIRE VIO/WHT WIRE W/ SPECIAL EQUIPMENT W/O SPECIAL EQUIPMENT WHT WIRE WHT/GRN WIRE YEL/BLU WIRE YEL/GRY WIRE

BATTERY FUSE BLOCK BLK WIRE BLU WIRE BLU/WHT WIRE BODY CONTROL MODULE (UNDER LEFT SIDE OF DASH) CAMPER/ COMPUTER DATA LINES SYSTEM GRN/BLU WIRE GRN/VIO WIRE GROUND DISTRIBUTION SYSTEM GRY/BRN WIRE HI SPD GMLAN SER DATA (+) 1 HOT AT ALL TIMES LEFT TRAILER TURN SIG LAMP LIN BUS 2 RED/GRN WIRE RED/VIO WIRE RED/YEL WIRE RIGHT TRAILER TURN SIG LAMP TRAILER AUXILARY CONTROL TRAILER BRAKE APPLY SIG TRAILER BRAKE POWER CONTROL MODULE TRAILER BRAKES PROVISION (BLUNT CUT) (UNDER LEFT SIDE OF INSTRUMENT PANEL) TRAILER CONNECTOR UNDERHOOD FUSE BLOCK W/ INTEGRATED TRAILER BRAKE CONTROL W/ SPECIAL EQUIPMENT W/ TRAILER HITCH PREPARATION PACKAGE W/O INTEGRATED TRAILER BRAKE CONTROL W/O SPECIAL EQUIPMENT W/O TRAILER HITCH PREPARATION PACKAGE WHT WIRE WHT/BLU WIRE WHT/GRN WIRE YEL/BLU WIRE YEL/GRY WIRE

BACKUP LAMPS CIRCUIT BLU WIRE BLU/WHT WIRE BLUNT CUT) GRN/VIO WIRE GRN/WHT WIRE GRY/BRN WIRE LEFT TRAILER STOP/TURN SIGNAL LAMP RELAY PARK LAMPS RELAY RED/GRN WIRE RED/VIO WIRE RED/YEL WIRE RIGHT TRAILER STOP/TURN SIGNAL LAMP RELAY TRAILER BACKUP LAMPS RELAY TRAILER CAMPER PROVISION UNDERHOOD FUSE BLOCK W/ SPECIAL EQUIPMENT W/ TRAILER HITCH PREPARATION PACKAGE W/O SPECIAL EQUIPMENT W/O TRAILER HITCH PREPARATION PACKAGE WHT/GRN WIRE YEL/BLU WIRE YEL/GRY WIRE

BATT POS VOLT 56 BLK WIRE BLU WIRE COMPUTER DATA LINES SYSTEM EXTERIOR LAMPS CIRCUIT GND 17 GRN WIRE GRN/VIO WIRE GRN/WHT WIRE GRY/BRN WIRE HOT W/ IGNITION MAIN RELAY ENERGIZED IGN 1 VOLT 4 LAMP CTRL LOW SPD GMLAN SERIAL DATA RED/GRN WIRE RED/VIO WIRE RED/YEL WIRE RLY COIL CTRL SECONDARY FUSED BATTERY POSITIVE VOLTAGE 58 TRAILER BACKUP LAMP CTRL TRAILER CONNECTOR TRAILER LIGHTING CONTROL MODULE TRAILER PARK LAMP CTRL UNDERHOOD FUSE BLOCK VIO/GRN WIRE VIO/WHT WIRE W/ SPECIAL EQUIPMENT W/O SPECIAL EQUIPMENT WHT WIRE WHT/GRN WIRE YEL/BLU WIRE YEL/GRY WIRE