Buick LaCrosse II (2009-2013) (left front of engine compt) Wiring diagrams

A/C COMPRESSOR SOLENOID VALVE AIR QUALITY SENSOR (BELOW AIR INLET GRILL PANEL) BLK WIRE BLK/DK BLU WIRE BLOWER MTR SPD CTRL BRN/VIO WIRE BRN/YEL WIRE COMPUTER DATA LINES SYSTEM COOLING FAN LOW SPEED RELAY DEFOGGER SYSTEM DK BLU WIRE DK BLU/LT GRN WIRE FUSE GRN WIRE GRN/YEL WIRE GRY WIRE GRY/DK BLU WIRE GRY/LT GRN WIRE HOT AT ALL TIMES HOT W/ ENGINE CONTROLS IGNITION RELAY ENERGIZED HOT W/ IGNITION MAIN RELAY ENERGIZED HUMIDITY SENS SIG TWILIGHT SENTINEL DELAY SIG HVAC CONTROL MODULE INSIDE AIR TEMP SENS LOW REF REAR DEFOG RLY CTRL LEFT COOLING FAN HIGH SPEED RELAY LINEAR INTERCONNECT NETWORK BUS 9 LOGIC LT GRN DK BLU/ WIRE LT GRN/VIO WIRE RED/VIO WIRE RED/WHT WIRE RIGHT COOLING FAN HIGH SPEED RELAY SOLAR SENS DRV SIG TEMP SENS LOW REF UNDERHOOD FUSE BLOCK (LEFT SIDE OF BATTERY) VIO/BLK WIRE VIO/GRY WIRE VIO/WHT WIRE WHT WIRE WHT/DK BLU WIRE YEL WIRE YEL/DK BLU WIRE YEL/RED WIRE

2501 2500 COMPUTER DATA LINES SYSTEM 40 39 55 42 GMLAN SERIAL DATA (-) GMLAN SERIAL DATA (+) 44 82 24 8 SENS LO REF ENG TEMP SENS SIG 52 59 42 56 46 45 BATT + VOLT LO SPD FAN RLY CTRL HI SPD FAN RLY CTRL BLK WIRE BLK/LT GRN WIRE BLK/WHT WIRE BRN/YEL WIRE COOLING FAN LOW SPEED RELAY DK BLU WIRE ENGINE CONTROL MODULE (LEFT FRONT OF ENGINE COMPT) ENGINE CONTROL MODULE RELAY FUSE GRY WIRE HOT AT ALL TIMES LEFT COOLING FAN HIGH SPEED RELAY LEFT COOLING FAN MOTOR LT GRN/PPL WIRE OF BATTERY) RED/BRN WIRE RED/WHT WIRE RIGHT COOLING FAN HIGH SPEED RELAY RIGHT COOLING FAN MOTOR UNDERHOOD FUSE BLOCK (LEFT SIDE WHT WIRE WHT/DK BLU WIRE YEL WIRE

BATTERY FUSE BLOCK BLK WIRE BRN WIRE BRN/VIO WIRE BRN/YEL WIRE DRIVER OUTSIDE REARVIEW MIRROR FUSE FUSE (TOP OF BATTERY) HOT AT ALL TIMES HVAC CONTROL MODULE LEFT REAR WINDOW DEFOGGER NOISE FILTER PASSENGER OUTSIDE REARVIEW MIRROR REAR DEFOGGER GRID REAR DEFOGGER IND REAR DEFOGGER RELAY REAR DEFOGGER RLY CTRL REAR DEFOGGER SWITCH LOGIC RED WIRE RIGHT REAR WINDOW DEFOGGER NOISE FILTER UNDERHOOD FUSE BLOCK (LEFT SIDE OF BATTERY) VIO WIRE YEL BRN/ WIRE

12 24 HAZ SW LEFT TURN SIG HAZ SW RIGHT TURN SIG PPL 22 17 4 19 HEADLAMP SW PARK LP SIG HAZ LED DIMMING SIG B+ BRK APPLY SENS LO REF BLK WIRE BODY CONTROL MODULE (LEFT SIDE OF DASH) BRN WIRE CENTER HIGH MOUNTED STOP LAMP COMPUTER DATA LINES SYSTEM DK BLU WIRE DK BLU/VIO WIRE DK BLU/WHT WIRE DK GRN WIRE FUSE GRN WIRE GRN/YEL WIRE GRY WIRE GRY/BRN WIRE GRY/YEL WIRE HAZARD SWITCH HEAD PARK AUTO HEADLAMP SWITCH HOT AT ALL TIMES INSTRUMENT PANEL FUSE BLOCK (LOWER LEFT SIDE OF DASH) INSTRUMENT PANEL MULTI-FUNCTION SWITCH 1 LEFT FRONT SIDE MARKER LAMP LEFT LICENSE PLATE LAMP LEFT PARK/ TURN SIGNAL LAMP LEFT REAR TURN SIGNAL LAMP LEFT TAIL LAMP LEFT TAIL/ STOP LAMP LEFT REAR SIDE MARKER LAMP LT BLU WIRE LT GRN WIRE LT GRN/RED WIRE LT GRN/VIO WIRE LT GRN/WHT WIRE OFF PPL RED WIRE RED/ LT BLU WIRE RED/BRN WIRE RED/DK GRN WIRE RED/LT GRN WIRE RED/WHT WIRE RIGHT LICENSE PLATE LAMP VIO/GRY WIRE W/ HID W/O HID WHT WIRE WHT/ DK BLU WIRE WHT/YEL WIRE

18 12 RR STATUS SIG LR STATUS SIG 25 27 16 RCDLR POWER RCDLR DATA TRANSMIT RCDLR GROUND 3 4 19 15 POS VOLT POS VOLT LOCK SIG UNLOCK SIG 4 1 UNLOCK CTRL LOCK CTRL 2 4 6 NETWORK BUS 3 AJAR SW SIG AJAR SW SIG 1 AMBIENT LIGHT/ SUNLOAD SENSOR (CENTER OF DASH) BLK WIRE BODY CONTROL MODULE (LEFT SIDE OF DASH) BRN WIRE BRN/LT GRN WIRE BRN/YEL WIRE COMPUTER DATA LINES SYSTEM DK BLU WIRE DK BLU/VIO WIRE DK BLU/WHT WIRE DRIVER DOOR LATCH ASSEMBLY DRIVER WINDOW MOTOR (DRIVER'S DOOR) DRIVER WINDOW SWITCH FUSE GRN WIRE GRN/GRY WIRE GRN/YEL WIRE GRY WIRE GRY/LT GRN WIRE GRY/WHT WIRE HOOD AJAR SW SIG HOOD AJAR SWITCH (FRONT OF ENGINE COMPT) HOT AT ALL TIMES HVAC CONTROL MODULE INSTRUMENT PANEL FUSE BLOCK (LOWER LEFT SIDE OF DASH) FUSE INSTRUMENT PANEL MULTI-FUNCTION SWITCH 1 LOCK CTRL 2 LOCK RELAY CTRL NETWORK BUS 3 NETWORK BUS 4 PASSENGER DOOR LATCH ASSEMBLY PPL RCDLR DATA RECEIVE RED WIRE RED/VIO WIRE SECURITY IND CTRL STATUS CTRL UNLOCK SIG VIO/GRY WIRE VIO/YEL WIRE WHT/VIO WIRE YEL WIRE YEL/LT GRN WIRE

4 2 1 3 ACTR SPLY VOLT ACTR RECEIVE SIG ACTR RTN ACTR TRANSMIT SIG AJAR SW SIG BLK WIRE BRN WIRE BRN/WHT WIRE BRN/YEL WIRE COMPUTER DATA LINES SYSTEM DK BLU WIRE DOOR LOCK SECURITY RELAY DRIVER INFORMATION SECURITY CENTER IND DISPLAY FLOW CONTROL MODULE CONNECTOR) GMLAN SERIAL DATA LOGIC GRN WIRE GRN/GRY WIRE GRN/YEL WIRE GRY WIRE GRY/BLK WIRE GRY/LT GRN WIRE INSTRUMENT CLUSTER KEYLESS ENTRY ANTENNA LEFT REAR DOOR LATCH ASSEMBLY LEFT REAR WINDOW SWITCH NETWORK BUS 3 NETWORK BUS 4 PASSENGER WINDOW MOTOR (FRONT PASSENGER'S DOOR) REMOTE CONTROL DOOR LOCK RECEIVER (RIGHT SIDE OF DASH) RIGHT REAR DOOR LATCH ASSEMBLY RIGHT REAR WINDOW SWITCH VIO/GRY WIRE VIO/YEL WIRE WHT/BLU WIRE WHT/DK BLU WIRE YEL WIRE

ACCESSORY VOLTAGE AJAR SW SIG AMBIENT LIGHT/ SUNLOAD SENSOR (CENTER OF DASH) BATT POS VOLT BLK WIRE BODY CONTROL MODULE (BCM) (LEFT SIDE OF DASH) BRN WIRE BRN/LT GRN WIRE BRN/VIO WIRE BRN/WHT WIRE COMPUTER DATA LINES SYSTEM DK BLU WIRE DK GRN WIRE DR LK CTRL DRV DR LK SW LK SIG DRV DR LK SW UNLK SIG DRV DR LK UNLK CTRL FUSE GRN/GRY WIRE GRN/YEL WIRE GRY WIRE HDLP HI BEAM RLY CTRL HEADLIGHTS SYSTEM HOOD AJAR SW SIG HOOD AJAR SWITCH (FRONT OF ENGINE COMPT) HORN RLY CTRL HORNS SYSTEM HOT AT ALL TIMES HVAC CONTROL MODULE INSTRUMENT PANEL FUSE BLOCK (LOWER LEFT SIDE OF DASH) INSTRUMENT PANEL MULTI-FUNCTION SWITCH 1 LK MTR STATUS SIG LR LK MTR STATUS SIG RR NETWORK BUS 4 POS VOLT PPL RED/WHT WIRE RIGHT REAR WINDOW SWITCH RUN/CRANK IGN 1 VOLT SECURITY IND CTRL UNDERHOOD FUSE BLOCK (LEFT SIDE OF BATTERY) VIO/BLK WIRE VIO/DK BLU WIRE VIO/GRY WIRE VIO/YEL WIRE WHT WIRE YEL WIRE YEL/BLK WIRE

BATTERY BLK WIRE BODY CONTROL MODULE BRAKE BOOSTER PUMP MOTOR RELAY BRN WIRE COOLING FAN RELAY DOOR LOCK RELAY GRY/BLU WIRE HOOD AJAR SWITCH HORN ASSEMBLY IGNITION COIL 5 IGNITION COIL 6 IGNITION IGNITION COIL 1 COIL 3 IGNITION IGNITION COIL 2 COIL 4 IGNITION MAIN RELAY LEFT COOLING FAN DIODE LEFT DAYTIME RUNNING LAMP, LEFT FRONT FOG LAMP LEFT HEADLAMP LEFT HEADLAMP BALLAST LEFT LEFT PARK/ FRONT TURN SIDE SIGNAL MARKER LAMP LAMP LOW SPEED COOLING FAN DIODE PASSENGER PRESENCE (PASSENGER SEAT HARNESS, DETECTION MODULE APPROXIMATELY PASSENGER WINDOW MOTOR RESTRAINT SENSING, DIAGNOSTIC MODULE) RIGHT COOLING FAN DIODE RIGHT HEADLAMP RIGHT REAR WINDOW SWITCH RIGHT RIGHT PARK/ FRONT TURN SIDE SIGNAL MARKER LAMP LAMP W/ FRONT FOG LAMPS W/ FRONT W/O FRONT FOG LAMP FOG LAMP, HID, HID W/ HID W/ HID LEFT LEFT HIGH HEADLAMP BEAM HORIZONTAL SOLENOID MOTOR ACTUATOR W/ HID W/O HID W/O FRONT W/ FRONT FOG LAMPS FOG LAMPS W/O HID WINDSHIELD WASHER FLUID LEVER SENSOR WINDSHIELD WASHER PUMP RELAY WINDSHIELD WIPER RELAY

1 2 33 32 RF DRL SPLY VOLT LF DRL SPLY VOLT 2 3 2540 2140 B+ B+ 22 10 5060 278 LOW SPD GMLAN SER DATA AMBIENT LIGHT SENS SIG 22 11 16 13 306 103 HDLP SW PARK LP SIG ADAPTIVE FRONT LIGHTING CIRCUIT AMBIENT LIGHT/ SUNLOAD SENSOR (CENTER OF DASH) BLK WIRE BODY CONTROL MODULE (LEFT SIDE OF DASH) BRN WIRE BRN/VIO WIRE BRN/WHT WIRE BRN/YEL WIRE COMPUTER DATA LINES SYSTEM CRUISE CONTROL, SOUND SYSTEMS DK BLU WIRE DK BLU/BRN WIRE FRONT FOG LAMP FUSE FUSE FUSE GRN WIRE GRY WIRE GRY/DK BLU WIRE HDLP DIMMER SW HI BEAM SIG HDLP OFF SIG CTRL HDLP SW ON SIG HDLP SW FLASH TO PASS SIG HEADLAMP HIGH BEAM RELAY HEADLAMP LOW BEAM RELAY HIGH LOW FTP HOT AT ALL TIMES HOT AT ALL TIMES BATTERY FUSE BLOCK FUSE (TOP OF BATTERY) HVAC CONTROL MODULE INSTRUMENT PANEL FUSE BLOCK (LOWER LEFT SIDE OF DASH) LEFT DAYTIME RUNNING LAMP (BOTTOM OF "A" PILLAR) LEFT HEADLAMP LEFT HIGH BEAM SOLENOID ACTUATOR LEFT LOW BEAM HEADLAMP LIGHTING CTRL SW REF LIGHTING CTRL SW SIG LOW REF LT GRN WIRE NCA WIRE RED WIRE RED/BLK WIRE RELAY RIGHT DAYTIME RUNNING LAMP RIGHT HEADLAMP RIGHT HEADLAMP BALLAST RIGHT HIGH BEAM SOLENOID ACTUATOR RIGHT LOW BEAM HEADLAMP TURN SIGNAL/ MULTI-FUNCTION SWITCH UNDERHOOD FUSE BLOCK (LEFT SIDE OF BATTERY) VIO WIRE WHT WIRE YEL WIRE

BATT POS VOLT BLK WIRE BODY CONTROL MODULE (LEFT SIDE OF DASH) BRN/LT GRN WIRE COMPUTER DATA LINES SYSTEM DK GRN (OR LT GRN) WIRE FUSE OF BATTERY) GRN/PPL WIRE GRY WIRE HOOD AJAR SW SIG HOOD AJAR SWITCH (FRONT OF ENGINE COMPT) HOT AT ALL TIMES IMMOBILIZER CONTROL MODULE (CENTER CONSOLE) LT GRN WIRE LT GRN/VIO WIRE NETWORK BUS 11 PPL RED/WHT WIRE UNDERHOOD FUSE BLOCK (LEFT SIDE VEH IMMOBILIZER RTN VEH SPLY VOLT YEL WIRE