GMC Cab & Chassis Sierra 3500 (2004-2007) headlamp switch Wiring diagrams

22 20 5 8 19 CLASS 2 DATA LOW REF DOOR AJAR SIG CTSY LAMP POWER CTSY LAMP CTRL 22 3 18 13 4 CLASS 2 DATA LOW REF DOOR AJAR SIG CTSY LAMP POWER CTSY LAMP CTRL BATTERY B+ CTSY LAMP SUPPLY BATTERY B+ INADVERTENT PWR SUPPLY BLK WIRE BLK/WHT WIRE BODY CONTROL MODULE (LOWER LEFT SIDE OF DASH, BELOW STEERING COLUMN) BRN WIRE CLASS 2 SERIAL DATA CONVENIENCE PACKAGE COMFORT, DECOR LEVEL #3 CTSY LAMP ON SIG DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DOME LAMP SWITCH DOOR LATCH ASSEMBLY (LR) (CREW CAB) DOOR LATCH ASSEMBLY (PASSENGER) DOOR LATCH ASSEMBLY (RR) (CREW CAB) DOOR LATCH ASSEMBLY- DRIVER DRIVER DOOR MODULE (DDM) (IN LEFT FRONT DOOR) FRONT DOOR COURTESY LAMP (LEFT) FRONT DOOR COURTESY LAMP (RIGHT) FRONT PASSENGER DOOR MODULE (FPDM) (IN RIGHT FRONT DOOR) FUSE FUSE GRY/BLK WIRE HEADLAMP SWITCH HOT AT ALL TIMES I/P FUSE BLOCK (LOWER LEFT SIDE OF DASH) I/P RELAY BLOCK (NEAR LEFT KICK PANEL) INTERIOR LAMP DEFEAT SWITCH JUNCTION I/P BLOCK (RIGHT SIDE OF DASH, BEHIND ACCESS PANEL) LF DOOR AJAR SIG CARGO LAMP LOW CTRL RF DOOR AJAR SIG LT BLU WIRE LT BLU/BLK WIRE LT GRN WIRE LT GRN/BLK WIRE MERCHANDISED PACKAGE LUXURY EDITION ORG/ WIRE PPL PPL INT LAMP DEFEAT SIG RR DOOR AJAR SIG LR DOOR AJAR SIG TAN WIRE WHT WIRE

22 3 18 4 13 CLASS 2 DATA LOW REF DOOR AJAR SIG CTSY LAMP CTRL CTSY LAMP POWER BLK WIRE BLK/WHT WIRE BODY CONTROL MODULE (LOWER LEFT SIDE OF DASH, BELOW STEERING COLUMN) BRN WIRE CARGO LAMP LOW CTRL RF DOOR AJAR SIG LF DOOR AJAR SIG CTSY LAMP ON SIG CLASS 2 SERIAL DATA CONVENIENCE PACKAGE COMFORT AND DECOR LEVEL #3 CREW CAB CREW CAB ONLY CTSY LAMP SUPPLY DK BLU WIRE DK BLU/WHT WIRE DOME LAMP SWITCH DRIVER DOOR LATCH ASSEMBLY DRIVER DOOR MODULE (DDM) (IN LEFT FRONT DOOR) GRY/BLK WIRE HEADLAMP SWITCH INADVERTANT PWR SUPPLY LEFT FRONT DOOR COURTESY LAMP LEFT REAR DOOR COURTESY LAMP (2003) LEFT REAR DOOR LATCH ASSEMBLY LT BLU/BLK WIRE LT GRN WIRE LT GRN/BLK WIRE MERCHANDISED PACKAGE LUXURY EDITION ORG/ WIRE PPL INT LAMP DEFEAT SIG PPL INT LAMP DEFEAT SW REAR DOME LAMP RIGHT REAR DOOR COURTESY LAMP (2003) RIGHT REAR DOOR LATCH ASSEMBLY RR DOOR AJAR SIG LR DOOR AJAR SIG TAN WIRE

AUTO PARK BACK-UP LAMPS CIRCUIT BLK WIRE BLK/WHT WIRE BLU WIRE BLUNT CUT (W/ CAMPER BLUNT CUT) BODY CONTROL MODULE (BCM) (ON LOWER LEFT SIDE OF DASH, BELOW STEERING COLUMN) BRN WIRE COMPUTER DATA LINES SYSTEM DK BLU WIRE DK GRN WIRE DK LT EMERGENCY VEHICLE ROOF LAMP RELAY FRT PARK FUSE GRN WIRE GRY WIRE GRY/BLK WIRE HARN, NEAR TRAILER CONNECTOR BREAKOUT) HAZARD SWITCH HEAD HEADLAMP SWITCH HOT AT ALL TIMES HOT IN RUN, START I/P RELAY BLOCK IGN E FUSE LEFT FRONT MARKER LAMP LEFT FRONT PARK/ TURN SIGNAL LAMP LEFT RIGHT LT BLU WIRE LT GRN WIRE OFF PARK LP RELAY PNK WIRE PRK LMP ON RED WIRE RIGHT FRONT MARKER LAMP RIGHT FRONT PARK/ TURN SIGNAL LAMP SERIAL DATA PRK LMP RLY STUD 1 FUSE STUD 2 FUSE TAN WIRE TO TRL PARK FUSE TRAILER CONNECTOR TURN SIGNAL/ MULTI-FUNCTION SWITCH UNDER- HOOD FUSE BLOCK (ON LEFT SIDE OF ENGINE COMPT) WHEEL TRAILER WIRING PROVI- SIONAL) WHT WIRE YEL WIRE

AUDIO AMPLIFIER BACK-UP ALARM BACKUP LAMP (LEFT) BACKUP LAMP- RIGHT BLK WIRE BLK/WHT WIRE CAMPER/ CHEVY GMC CHEVY GMC CLEARANCE LAMPS CRUISE CONTROL MODULE DATA LINK CONNECTOR DIGITAL RADIO RECEIVER EXCEPT LUXURY FOUR WHEEL STEERING FOUR WHEEL STEERING FROM I/P RELAY BLOCK (DIAGRAM 3 OF 4) HAZARD LAMPS SWITCH HEADLAMP SWITCH HVAC BODY CONTROL CONTROL MODULE MODULE I/P FUSE BLOCK (LOWER LEFT SIDE OF DASH) I/P JUNCTION BLOCK (RIGHT SIDE OF DASH) I/P RELAY BLOCK (NEAR LEFT KICK PANEL) I/P RELAY BLOCK (NEAR LEFT KICK PANEL) TO I/P RELAY BLOCK (DIAGRAM 3 OF 4) IGNITION KEY ALARM TOW/HAUL SWITCH SWITCH INFLATABLE RESTRAINT STEERING WHEEL MODULE COIL LEFT LEFT REAR TURN SIGNAL LAMP LICENSE LAMP (RIGHT) LICENSE LAMP- LEFT LUXURY (IN CONSOLE HARNESS) MULTI- TRACTION FUNCTION CONTROL ACCESSORY SWITCH SWITCH NCA WIRE RADIO TURN SIGNAL/ HAZARD FLASHER MODULE REAR LAMPS JUNCTION BLOCK (INSIDE OF LEFT REAR FRAME RAIL) REMOTE PLAYBACK DEVICE REAR SEAT (CD AUDIO AUDIO PLAYER) AMPLIFIER CONTROLLER RIGHT RIGHT REAR TURN SIGNAL LAMP STEERING TRANSMISSION WHEEL SHIFT SPEED/ POSITION SELECT SENSOR SWITCH TAIL/STOP LAMP (LEFT) TAIL/STOP LAMP-RIGHT) TAILGATE MARKER LAMP TAN WIRE TRAILER WIRING PROVISION TRANSFER CASE SHIFT CONTROL MODULE DIGITAL RADIO RECEIVER TURN SIGNAL/ MULTIFUNCTION SWITCH VEHICLE REAR SEAT COMMUNICATION ENTERTAINMENT INTERFACE ASSEMBLY MODULE WHT WIRE WINDOW/ DOOR LOCK SWITCH (PASSENGER)

A/T SHIFT LOCK SOLENOID AUTO A/C AUXILIARY POWER OUTLET (BIN) AUXILIARY POWER OUTLET (CONSOLE) AUXILIARY POWER OUTLET (FRONT) BLK WIRE BLOWER MOTOR CONTROL PROCESSOR BLOWER MOTOR RESISTOR ASSEMBLY CIGAR LIGHTER CLEARANCE LAMPS DOME CENTER LAMP HIGH (FRONT) MOUNTED STOP LAMP EXC LUXURY HD TRAILERING ROOF EQUIPMENT MARKER PROVISION LAMP (LEFT) HEADLAMP SWITCH HVAC CONTROL MODULE I/P FUSE BLOCK (LOWER LEFT SIDE OF DASH) I/P JUNCTION BLOCK (LOWER RIGHT SIDE OF DASH) I/P RELAY BLOCK (NEAR LEFT KICK PANEL) INSIDE REARVIEW MIRROR LUXURY MAN A/C OVERHEAD CONSOLE PNK WIRE REAR WHEEL STEERING SWITCH RIGHT COOLING FAN RECIRCULATION ACTUATOR ROOF MARKER LAMP (RIGHT) SUNROOF SUNROOF CONTROL SWITCH MODULE DATA LINK CONNECTOR UNDERHOOD COOLING FAN FUSE BLOCK (LEFT SIDE OF ENGINE COMPT) COOL/FAN RELAY VANITY DOME/ READING MIRROR LAMP LAMP (REAR) (RIGHT) VANITY MIRROR LAMP (LEFT) W/ 5 LAMP ROOF MARKER W/O 5 LAMP ROOF MARKER WINDSHIELD WIPER INSTRUMENT MOTOR PANEL MODULE CLUSTER

AUDIO AMPLIFIER BACK-UP ALARM BACKUP LAMP (LEFT) BACKUP LAMP- RIGHT BLK WIRE BLK/WHT WIRE CAMPER/ CHEVY GMC CHEVY GMC CLEARANCE LAMPS CRUISE CONTROL MODULE DATA LINK CONNECTOR EXCEPT DUAL WHEELS DUAL WHEELS (IN STEERING WHEEL CONTROLS HARNESS) EXCEPT LUXURY FROM I/P RELAY BLOCK (DIAGRAM 3 OF 4) HAZARD LAMPS SWITCH HEADLAMP DIMMER SWITCH HEADLAMP SWITCH I/P FUSE BLOCK (LOWER LEFT SIDE OF DASH) I/P JUNCTION BLOCK (RIGHT SIDE OF DASH) I/P RELAY BLOCK (NEAR LEFT KICK PANEL) I/P RELAY BLOCK (NEAR LEFT KICK PANEL) TO I/P RELAY BLOCK (DIAGRAM 3 OF 4) IGNITION KEY ALARM SWITCH TOW/HAUL SWITCH INFLATABLE RESTRAINT STEERING WHEEL MODULE COIL INSTRUMENT PANEL CLUSTER TIRE PRESSURE MONITOR MODULE LEFT FRONT RIGHT REAR LEFT REAR LEFT REAR TURN SIGNAL LAMP LICENSE LAMP (RIGHT) LICENSE LAMP- LEFT LUXURY (IN CONSOLE HARNESS) MULTI- FUNCTION ACCESSORY SWITCH TRACTION CONTROL SWITCH NCA WIRE RADIO TURN SIGNAL/ HAZARD FLASHER MODULE REAR LAMPS JUNCTION BLOCK (INSIDE OF LEFT REAR FRAME RAIL) REAR SEAT AUDIO CONTROLLER REAR SEAT AUDIO CONTROLLER AUDIO AMPLIFIER REMOTE PLAYBACK DEVICE (CD PLAYER) (EXCEPT LUXURY) DIGITAL RADIO RECEIVER RIGHT FRONT RIGHT REAR TURN SIGNAL LAMP TAIL/STOP LAMP (LEFT) TAIL/STOP LAMP-RIGHT) TAILGATE MARKER LAMP TAN WIRE TRAILER WIRING PROVISION TRANSFER CASE SHIFT CONTROL MODULE TURN SIGNAL/ MULTIFUNCTION SWITCH VEHICLE COMMUNICATION INTERFACE MODULE REAR SEAT ENTERTAINMENT ASSEMBLY W/ DUAL WHEELS WHT WIRE WINDOW/ DOOR LOCK SWITCH (PASSENGER) WIPER SWITCH

A/T SHIFT LOCK SOLENOID AUTO A/C AUXILIARY POWER OUTLET (BIN) AUXILIARY POWER OUTLET (CONSOLE) AUXILIARY POWER OUTLET (FRONT) BLK WIRE BLOWER MOTOR CONTROL PROCESSOR BLOWER MOTOR RESISTOR ASSEMBLY CIGAR LIGHTER CLEARANCE LAMPS DATA LINK CONNECTOR DOME LAMP (FRONT) CENTER HIGH MOUNTED STOP LAMP DOME/ READING LAMP (REAR) VANITY MIRROR LAMP (RIGHT) EXC LUXURY HD TRAILERING EQUIPMENT PROVISION ROOF MARKER LAMP (LEFT) HEADLAMP SWITCH HVAC CONTROL MODULE I/P FUSE BLOCK (LOWER LEFT SIDE OF DASH) I/P JUNCTION BLOCK (LOWER RIGHT SIDE OF DASH) I/P RELAY BLOCK (NEAR LEFT KICK PANEL) INSIDE REARVIEW MIRROR LOCK RELAY UNLOCK RELAY LUXURY MAN A/C OVERHEAD CONSOLE PNK WIRE REAR WHEEL STEERING SWITCH RECIRCULATION ACTUATOR RIGHT COOLING FAN ROOF MARKER LAMP (RIGHT) SUNROOF CONTROL MODULE SUNROOF SWITCH SWITCH UNDERHOOD COOLING FAN FUSE BLOCK (LEFT SIDE OF ENGINE COMPT) COOL/FAN RELAY 3 VANITY MIRROR LAMP (LEFT) W/ 5 LAMP ROOF MARKER W/O 5 LAMP ROOF MARKER WINDSHIELD WIPER MOTOR MODULE INSTRUMENT PANEL CLUSTER

AMBIENT LIGHT SENSOR (ON TOP CENTER OF DASH) (EXC AUTO A/C) AMBIENT LIGHT SUNLOAD SENSOR ASSEMBLY (TOP OF INSTRUMENT PANEL) (AUTO A/C) BLK WIRE BLK/WHT WIRE BODY CONTROL MODULE (BCM) (ON LOWER LEFT SIDE OF DASH, BELOW STEERING COLUMN) DAYTIME RUNNING LAMP (LEFT) DAYTIME RUNNING LAMP (RIGHT) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE DRL DEFEAT DRL FUSE DRL RELAY FLASH TO PASS FOG LAMP (LF) FOG LAMP (RF) FOG LAMP SWITCH FOG LP FUSE FOG LP RELAY GASOLINE DIESEL GRY/BLK WIRE HDLP LOW RELAY HDLP-HI RELAY HEAD PARK AUTO HEAD- LAMP - HIGH BEAM (LEFT) HEAD- LAMP - HIGH BEAM (RIGHT) HEAD- LAMP - LOW BEAM (LEFT) HEAD- LAMP - LOW BEAM (RIGHT) HEADLAMP SWITCH HI BM RLY CTRL LO BM RLY CTRL DRL RLY CTRL FOG LP RLY CTRL HI HDLP LT FUSE HI HDLP RT FUSE HI/LO BEAM SELECT HLPS ON SIG FLASH TO PASS PK BRAKE SIG LOW REF HOT AT ALL TIMES I/P RELAY BLOCK (NEAR LEFT KICK PANEL) LO HDLP LT FUSE LO HDLP RT FUSE LT BLU WIRE LT GRN WIRE LT GRN/BLK WIRE MULTIFUNCTION ACCESSORY SWITCH ORG/ WIRE PARK BRAKE SWITCH (PART OF PARK BRAKE ASSEMBLY) PARK LP SW SIG AMBIENT LT SENS DRL SW SIG FOG LP SW SIG HDLP DIM SW SIG PNK WIRE PNK/WHT WIRE PPL SOUND SYSTEM TAN WIRE TURN SIGNAL/ MULTIFUNCTION SWITCH UNDERHOOD FUSE BLOCK (LEFT SIDE OF ENGINE COMPT) WHT WIRE YEL WIRE YEL/BLK WIRE

2 HI IND CONTROL 2-HI IND 4 HI IND CONTROL 4 LO IND CONTROL 4-HI IND 4-LO IND AUTO BATTERY (B+) BLK WIRE BRN/WHT WIRE CREW CAB ONLY DIMMING INPUT DIMMING LO REF DK GRN/WHT WIRE DRL OFF ELECTRONIC POWER STEERING SYSTEM EXCEPT HYBRID FOG LAMP RLY CTRL DRL OFF IND CTRL HEADLAMP ON IND CTRL 5 VOLT REF PPL PNK WIRE FUSE GRY WIRE GRY/BLK WIRE HEADLAMP ON HEADLAMP SWITCH HOT AT ALL TIMES I/P FUSE BLOCK (LOWER LEFT SIDE OF DASH) IND INST PANEL DIMMING LED DIMMING SUPPLY I/P LAMPS DIM SUPPLY INSTRUMENT PANEL CLUSTER LEFT REAR WINDOW SWITCH LT GRN/BLK WIRE ORG/ WIRE ORG/BLK WIRE PNK AWD IND CONTROL WIRE PNK WIRE PPL PPL/WHT WIRE RED WIRE RIGHT REAR WINDOW SWITCH TAN/BLK WIRE TRANSFER CASE SHIFT CONTROL MODULE (BEHIND HEADLAMP SWITCH) TRANSFER CASE SHIFT CONTROL SWITCH

ANL/DRL DEFEAT AUTO BATTERY BATTERY BATTERY BATTERY GROUND BLK WIRE BLK/WHT WIRE BLU WIRE BODY CONTROL MODULE (BCM) (ON LOWER LEFT SIDE OF DASH, BELOW STEERING COLUMN) CREW CAB ONLY FUSE GROUND DISTRIBUTION SYSTEM GRY WIRE GRY/BLK WIRE HEAD PARK HEADLAMP SWITCH HOT AT ALL TIMES HOT IN ACC, RUN HOT IN ACC, RUN, START HOT IN RUN, START I/P FUSE BLOCK (ON LOWER LEFT SIDE OF DASH) I/P RELAY BLOCK (NEAR LEFT KICK PANEL) IGNITION KEY ALARM SWITCH LEFT REAR DOOR LATCH ASSEMBLY LT BLU WIRE LT BLU/BLK WIRE LT GRN WIRE LT GRN/BLK WIRE ORG/ WIRE ORG/BLK WIRE PARK BRAKE SWITCH (PART OF PARK BRAKE ASSEMBLY) PARK LAMP ON SIGNAL GROUND DIMMING INPUT PNK WIRE POWER DISTRIBUTION SYSTEM RIGHT REAR DOOR AJAR SW LEFT REAR DOOR AJAR SW RIGHT REAR DOOR LATCH ASSEMBLY SERIAL DATA TAN WIRE TBC ACCY FUSE TBC BATT FUSE TBC IGN 0 FUSE TBC IGN 1 FUSE UNDERHOOD FUSE BLOCK (AT LEFT SIDE OF ENGINE COMPARTMENT) WHT WIRE YEL WIRE