Buick LaCrosse III (2016-2019) logic Wiring diagrams

A/C COMPRESSOR A/C COMPRESSOR CLUTCH A/C COMPRESSOR CLUTCH RELAY A/C COMPRESSOR SOLENOID VALVE A/C HEV FUSE A/C ON IND A/C ON SWITCH AIR QUALITY SENSOR (BELOW AIR INLET GRILL PANEL) AUTO IND UPPER AIR OUTLET IND AUTO SWITCH BLK WIRE BRN/LT GRN WIRE COMPUTER DATA LINES SYSTEM DATA BUS 9 DK BLU/BRN WIRE DK BLU/YEL WIRE DK GRN/YEL WIRE DRIVER HEATED SEAT SWITCH DRIVER TEMPERATURE DISPLAY HOT AT ALL TIMES HOT W/ ENGINE CONTROLS IGNITION RELAY ENERGIZED HOT W/ IGNITION MAIN RELAY ENERGIZED HVAC CONTROLS IGN VOLT AIR QUALITY SENS SIG IP BODY IGN FUSE LEFT HIGH SEAT HEAT IND LEFT LOW SEAT HEAT IND LEFT MED SEAT HEAT IND LOGIC LOWER AIR OUTLET IND LOWER AIR OUTLET SWITCH LT GRN WIRE MAX IND MAX SWITCH PASSENGER HEATED SEAT SWITCH PASSENGER TEMPERATURE DISPLAY REAR DEFOGGER IND REAR DEFOGGER SWITCH RECIRCULATION IND RECIRCULATION SWITCH RED WIRE RED/LT BLU WIRE RED/WHT WIRE RIGHT HIGH SEAT HEAT IND RIGHT LOW SEAT HEAT IND RIGHT MED SEAT HEAT IND SERIAL DATA START STOP IND START/ STOP SWITCH SYNC SWITCH UNDERHOOD FUSE BLOCK UPPER AIR OUTLET SWITCH VIO/GRY WIRE VIO/WHT WIRE WHT/GRY WIRE WINDSHIELD DEFROST IND SYNC IND WINDSHIELD DEFROST SWITCH

AIR RECIRCULATION DOOR ACTUATOR BLK/YEL WIRE BLU/BRN WIRE BLU/YEL WIRE COMPUTER DATA LINES SYSTEM DRIVER INFORMATION CENTER DISPLAY ENGINE COOLANT TEMPERATURE GAUGE ENGINE COOLANT TEMPERATURE IND GRN WIRE GRY/GRN WIRE GRY/RED WIRE GRY/VIO WIRE INSTRUMENT CLUSTER LEFT AIR TEMPERATURE DOOR ACTUATOR LOGIC MODE DOOR ACTUATOR MOST SERIAL DATA (+) RED/WHT WIRE VIO/GRN WIRE WHT WIRE WHT/GRN WIRE WHT/GRY WIRE YEL/BLK WIRE YEL/BRN WIRE

A/C PRESS SENS A/C REFRIGERANT PRESS SENS SIG A/C REFRIGERANT PRESSURE SENSOR AIR TEMP SENS SIG AMBIENT AIR TEMPERATURE SENSOR BATT POS VOLT BATT POS VOLT COOLING FAN CTRL RELAY SPEED SIG BLK WIRE BLK/BLU WIRE BLK/BRN WIRE BLK/WHT WIRE BLU WIRE BLU/GRY WIRE BRN/RED WIRE CLUTCH RELAY CTRL COMPUTER DATA LINES SYSTEM COOL FAN FUSE DK BLU WIRE DK GRN WIRE EBOOST/COOL FAN LT FUSE ENG COOLANT TEMP SENS SIG ENGINE CONTROL MODULE (LEFT FRONT OF ENGINE COMPT) ENGINE COOLANT TEMPERATURE SENSOR FUSE 9 GROUND HI SPEED GMLAN SERIAL DATA (-) 1 HOT AT ALL TIMES INSTRUMENT PANEL FUSE BLOCK LEFT COOLING FAN MOTOR (BEHIND LEFT SIDE OF RADIATOR) LOGIC NCA WIRE RED/BRN WIRE RED/YEL WIRE RELAY SPEED SIG RIGHT COOLING FAN MOTOR (BEHIND RIGHT SIDE OF RADIATOR) SENS LOW REF SIG GROUND UNDERHOOD FUSE BLOCK WHT WIRE WHT/BLK WIRE WHT/GRY WIRE

BLU/GRN WIRE BLU/GRY WIRE DATA DATA BUS 10 DATA BUS 12 DATA BUS 2 DATA BUS 5 DK BLU WIRE DK BLU/VIO WIRE DK BLU/YEL WIRE DK GRN/BLK WIRE DK GRN/DK BLU WIRE DK GRN/WHT WIRE DK GRN/YEL WIRE GRY/LT GRN WIRE GRY/VIO WIRE HEAD-UP DISPLAY HI SPD GMLAN SERIAL DATA (+) 9 INFO DISPLAY MODULE INFOTAINMENT CONTROL TOUCHPAD INSTRUMENT CLUSTER LOGIC LIN SERIAL LO SPD GMLAN LOGIC LOW SPD GMLAN LOW SPD GMLAN SERIAL DATA 2 LT GRN WIRE MEDIA DISC PLAYER MOST CONTROL MOST SERIAL RADIO RIGHT STEERING WHEEL CONTROLS SWITCH LOGIC SERIAL DATA 2 SERIAL DATA COMM ENABLE STEERING WHEEL AIR BAG COIL TELEMATICS COMMUNICATION INTERFACE CONTROL MODULE VIO/YEL WIRE W/ INFOTAINMENT CONTROL TOUCHPAD W/ INFOTAINMENT CONTROL TOUCHPAD W/ ONSTAR W/O ONSTAR WHT WIRE WHT/DK BLU WIRE WHT/GRN WIRE WHT/GRY WIRE WHT/VIO WIRE

ACC WAKEUP SERIAL DATA ACCESSORY WAKEUP DATA BUS 21 DATA BUS 26 DK BLU WIRE DK BLU/BLK WIRE DK BLU/YEL WIRE DK GRN WIRE DK GRN/DK BLU WIRE ENGINE CONTROL MODULE HI SPD GMLAN HI SPD GMLAN SERIAL DATA (+) (3) HI SPD GMLAN SERIAL DATA (-) (1) HI SPD GMLAN SERIAL DATA (-) (2) LIN SERIAL LIN SERIAL DATA BUS 21 LIN SERIAL DATA BUS 26 LOGIC LOGIC ACTIVE GRILLE AIR SHUTTER MOTOR MODULE 1 LOGIC ACTIVE GRILLE AIR SHUTTER MOTOR MODULE 2 LOGIC TRANSMISSION CONTROL MODULE AUTOMATIC TRANSMISSION ASSEMBLY LT GRN/VIO WIRE NCA WIRE SERIAL DATA SERIAL DATA (-) (1) SERIAL DATA COMM ENABLE SUSPENSION CONTROL MODULE TRANSMISSION RANGE CONTROL MODULE (TOP OF TRANSMISSION) TRANSMISSION SHIFT LEVER TRANSMISSION SHIFT LEVER KNOB TRANSMISSION SHIFT LEVER POSITION INDICATOR LOGIC UNDERHOOD FUSE BLOCK (LEFT SIDE OF ENGINE COMPT) VIO/YEL WIRE WHT WIRE WHT/DK BLU WIRE

73 8 SIG GND ADAPTIVE CRUISE IND APP LO REF (1) APP LOW REF 2 APP SIG (1) APP SIG (2) BATT POSITIVE VOLT BLK WIRE BLK/BRN WIRE BLK/DK BLU WIRE BLK/RED WIRE BLK/VIO WIRE BLK/WHT WIRE BLK/YEL WIRE BODY CONTROL MODULE (UNDER FLOOR CONSOLE) BRAKE APPLY SENS CTRL BRAKE APPLY SENS LOW REF BRAKE APPLY SENS SIG BRAKE PEDAL POSITION SENSOR (TOP OF BRAKE PEDAL ASSEMBLY) BRAKE POS SENS LOW REF BRAKE POS SENS SIG BRN WIRE BRN/RED WIRE BRN/WHT WIRE COMPUTER DATA LINES SYSTEM CRUISE IND CRUISE/ETC/TCC BRK SIG DATA 2 (+) DK BLU WIRE DK BLU/WHT WIRE DK BLU/YEL WIRE DK GRN/WHT WIRE DRIVER INFORMATION CENTER DISPLAY ECM IGN FUSE ENGINE CONTROL MODULE (LEFT FRONT OF ENGINE COMPT) FUSE 20 FUSE 5 GMLAN GRY WIRE GRY/LT GRN WIRE HIGH SPD GMLAN SERIAL DATA (+) 1 HOT AT ALL TIMES HOT W/ IGNITION MAIN RELAY ENERGIZED INSTRUMENT CLUSTER INSTRUMENT PANEL FUSE BLOCK LOGIC LOW SPD LT GRN/WHT WIRE MAIN RELAY FUSED SUPPLY 2 RED WIRE RED/BRN WIRE RED/WHT WIRE RED/YEL WIRE RUN/CRANK IGN 1 VOLT SERIAL SERIAL DATA (-) (1) SET/COAST/RESUME/ ACCELERATE SW THROTTLE ACTUATOR CTRL CLOSE THROTTLE ACTUATOR CTRL OPEN THROTTLE POS SENS LOW REF THROTTLE POS SENS SIG UNDERHOOD FUSE BLOCK UP/DOWN SW SIG VIO/LT GRN WIRE WHT WIRE WHT/BLU WIRE WHT/LT GRN WIRE WHT/RED WIRE YEL WIRE YEL/WHT WIRE

ADAPTIVE CRUISE SWITCH AUTOMATIC TRANSMISSION ASSEMBLY BLK/BRN WIRE BLK/DK BLU WIRE BLK/RED WIRE BLK/VIO WIRE BLK/YEL WIRE BLU WIRE BRN WIRE BRN/GRN WIRE BRN/RED WIRE BRN/WHT WIRE COMPUTER DATA LINES SYSTEM CRUISE SWITCH DK BLU WIRE DK BLU/WHT WIRE FORWARD COLLISION ALERT WARNING SWITCH GAP SWITCH GRY WIRE GRY/GRN WIRE HIGH SPD GMLAN SERIAL DATA (+) 1 LEFT STEERING WHEEL CONTROLS SWITCH LOGIC LT GRN/WHT WIRE NCA WIRE ON/OFF SWITCH OSS HIGH SIGNAL OSS LOW SIGNAL RED WIRE RED/WHT WIRE RES+ SET- STEERING WHEEL AIR BAG COIL TRANSMISSION CONTROL MODULE TRANSMISSION OUTPUT SHAFT SPEED SENSOR W/ ADAPTIVE CRUISE CONTROL W/O ADAPTIVE CRUISE CONTROL WHT WIRE WHT/RED WIRE YEL WIRE

BATTERY POSITIVE VOLT BLK WIRE BLK/GRN WIRE BLK/GRY WIRE BLU/GRY WIRE BRN/GRN WIRE BRN/LT BLU WIRE BRN/RED WIRE BRN/WHT WIRE COMPUTER DATA LINES SYSTEM DK BLU WIRE DK BLU/YEL WIRE DRIVER INFORMATION CENTER DISPLAY FT AXLE LEVEL SENS SIG FT LEVEL SENS LOW REF GMLAN SER DATA (-) (2) GMLAN SER DATA - (1) GRN/GRY WIRE GRY/LT BLU WIRE GRY/LT GRN WIRE GRY/VIO WIRE GRY/WHT WIRE HOT AT ALL TIMES INSTRUMENT CLUSTER LEFT FRONT SHOCK ABSORBER ACTUATOR LEFT FRONT SUSPENSION POSITION SENSOR LEFT REAR SHOCK ABSORBER ACTUATOR LF DAMPING SERVO CTRL LOGIC LOW SPEED GMLAN SERIAL DATA 2 LR DAMPING SERVO CTRL NCA WIRE RED/GRN WIRE RF ACCEL LOW REF RF DAMPING SERVO CTRL RF WHEEL ACCEL SIG RIGHT FRONT SHOCK ABSORBER ACTUATOR RIGHT FRONT SUSPENSION POSITION SENSOR RIGHT REAR SHOCK ABSORBER ACTUATOR RR DAMPING SERVO CTRL RR HTD SEAT/ BSM/ESS FAN FUSE SERIAL DATA COMM ENABLE SUSPENSION CONTROL MODULE UNDERHOOD FUSE BLOCK WHT WIRE WHT/DK BLU WIRE WHT/RED WIRE

BACKUP LAMPS CIRCUIT BLK WIRE BLK/BRN WIRE BLU/BRN WIRE BLU/GRN WIRE BRN/DK GRN WIRE COMPUTER DATA LINES SYSTEM CRN LT FUSE CRN RT FUSE DK BLU/WHT WIRE DK BLU/YEL WIRE DRIVER OUTSIDE REAR VIEW MIRROR COURTESY LAMP DRIVER OUTSIDE REAR- VIEW MIRROR GMLAN GRN WIRE GRN/VIO WIRE GRN/WHT WIRE GRN/YEL WIRE GRY WIRE GRY/BRN WIRE GRY/GRN WIRE GRY/LT GRN WIRE GRY/VIO WIRE GRY/YEL WIRE HAZARD SWITCH HAZARD WARNING SWITCH HOT AT ALL TIMES HOT W/ ENGINE CONTROLS IGNITION RELAY ENERGIZED INSTRUMENT CLUSTER LEFT AUXILIARY TAIL LAMP LEFT BACKUP LAMP LEFT CORNERING LAMP RELAY LEFT REAR COMPARTMENT LID TAIL LAMP ASSEMBLY LEFT REAR SIDE MARKER LAMP LEFT REAR TURN SIGNAL LAMP LEFT TAIL LAMP LEFT TAIL LAMP ASSEMBLY LEFT TAIL/STOP LAMP LEFT TURN IND LEFT TURN SIGNAL REPEATER LAMP LO SPD LOGIC LT GRN WIRE PARK LAMPS IND RED WIRE RED/BRN WIRE RIGHT CORNERING LAMP RELAY RIGHT TURN IND SER DATA (+) 2 UNDERHOOD FUSE BLOCK VIO WIRE VIO/GRY WIRE VIO/WHT WIRE WHT WIRE WHT/YEL WIRE YEL WIRE YEL/DK BLU WIRE YEL/GRY WIRE YEL/WHT WIRE

BATT POS VOLT BLK WIRE BODY CONTROL MODULE (UNDER FRONT CONSOLE) BRN/GRY WIRE COMPUTER DATA LINES SYSTEM DC DC BATT 2/AWD FUSE DELAY SWITCH DK BLU WIRE DK GRN/BRN WIRE DRIVER INFORMATION CENTER DISPLAY FRT WPR FUSE FUSE 20 FUSE 41 GRY WIRE GRY/LT GRN WIRE GRY/VIO WIRE HI SPD GMLAN SERIAL DATA (-) (1) HOT AT ALL TIMES INSTRUMENT CLUSTER INSTRUMENT PANEL FUSE BLOCK LIN SERIAL DATA BUS 1 LOGIC LOW SPD GMLAN SERIAL DATA 2 OFF MIST POWER SUPPLY TRANSFORMER RED/BRN WIRE RED/DK BLU WIRE RED/YEL WIRE SPLY VOLT 1 UNDERHOOD FUSE BLOCK W/O START/STOP SYSTEM W/ START/STOP SYSTEM WASH PUMP FUSE WASHER SWITCH WHT WIRE WINDSHIELD WASHER PUMP WINDSHIELD WASHER PUMP RELAY WINDSHIELD WASHER RLY CTRL WINDSHIELD WASHER SW SIG WINDSHIELD WIPER MOTOR WINDSHIELD WIPER MTR RLY COIL CTRL WINDSHIELD WIPER SW HI SIG WINDSHIELD WIPER SW LO REF WINDSHIELD WIPER SW LOW SIG WINDSHIELD WIPER/WASHER SWITCH WIPER SWITCH YEL WIRE