Buick LaCrosse II facelift (2013-2016) computer data lines system Wiring diagrams

1 2 3 4 5 6 7 8 9 10 11 12 13 14 B+ GND AUTOMATIC TRANSMISSION ASSEMBLY BCM 1 FUSE BLK WIRE BLK/WHT WIRE BLU WIRE BODY CONTROL MODULE (BCM) (LEFT SIDE OF DASH) COMPUTER DATA LINES SYSTEM CONTROL SOLENOID DRIVER INFORMATION CENTER (DIC) ENGINE CONTROL MODULE (ECM) (LEFT FRONT OF ENGINE COMPT) FUSE GMLAN SERIAL DATA BUS + GND OSS OSS RANGE HIGH LOW SIG P GRN WIRE GRY WIRE GRY/VIO WIRE HDLP SW HDLPS OFF SIG CTRL HI SPD GMLAN SER DATA (+) HI SPD GMLAN SER DATA (+) HI SPD GMLAN SER DATA (-) HOT AT ALL TIMES HOT AT ALL TIMES UNDERHOOD FUSE BLOCK (LEFT SIDE OF BATTERY) HOT W/ IGNITION MAIN RELAY ENERGIZED IGN IGN 1 VOLT WAKEUP SERIAL DATA HI SPD GMLAN SER DATA (-) INSTRUMENT CLUSTER INSTRUMENT PANEL FUSE BLOCK (LOWER LEFT SIDE OF DASH) ISS ISS HIGH LOW LOGIC GMLAN LOW REF P/N PARK/ NEUTRAL SIG GMLAN SERIAL DATA BUS- PC 1 SOLENOID PC 2 SOLENOID PC 3 SOLENOID PC 4 SOLENOID PC 5 SOLENOID POWER DISTRIBUTION SYSTEM PRESSURE CONTROL (PC) SOLENOID VALVE 1 PRESSURE CONTROL (PC) SOLENOID VALVE 2 PRESSURE CONTROL (PC) SOLENOID VALVE 3 PRESSURE CONTROL (PC) SOLENOID VALVE 4 PRESSURE CONTROL (PC) SOLENOID VALVE 5 RAP RELAY COIL CTRL RAP RLY COIL CTRL RED WIRE RED/LT GRN WIRE RED/WHT WIRE SHIFT SOLENOID (SS) VALVE 1 SHIFT SOLENOID (SS) VALVE 2 SS 1 SS 2 TCC SOLENOID TCM BATT FUSE TCM FSC IGN TFP 1 TFP 3 TFP 4 TFP 5 TFT TORQUE CONVERTER CLUTCH PRESSURE CONTROL SOLENOID VALVE TRANSMISSION CONTROL MODULE (TCM) TRANSMISSION FLUID PRESSURE SWITCH TRANSMISSION FLUID TEMPERATURE SENSOR TRANSMISSION INPUT SHAFT SPEED SENSOR (ISS) TRANSMISSION INTERNAL MODE SWITCH (IMS) TRANSMISSION MANUAL SHIFT SWITCH TRANSMISSION OUTPUT SHAFT SPEED SENSOR (OSS) TRANSMISSION SHIFT LEVER TRNS TRNS RANGE RANGE SIG B SIG A TRNS TRNS RANGE SIG C VALVE ASSEMBLY VIO WIRE VIO/BLK WIRE VIO/YEL WIRE WHT WIRE WHT/GRY WIRE YEL WIRE YEL/BLK WIRE

BLK WIRE BLU WIRE BLU/YEL WIRE COMPUTER DATA LINES SYSTEM DIFFERENTIAL CLUTCH PUMP (UNDER REAR OF VEHICLE ON DIFFERENTIAL) GMLAN DATA BUS+ GND B+ GMLAN DATA BUS- GMLAN DATA BUS- GND COMMUNICATION ENABLE HOT AT ALL TIMES AWD/ FUSE BLOCK SADS (LEFT SIDE OF FUSE BATTERY) NCA WIRE REAR DIFFERENTIAL CLUTCH CONTROL MODULE (MOUNTED TO REAR DIFFERENTIAL) REAR DIFFERENTIAL CLUTCH SOLENOID VALVE (ON REAR DIFFERENTIAL) REAR DRIVE CLUTCH SOLENOID VALVE RED WIRE RED/BLU WIRE RED/WHT WIRE UNDERHOOD WHT WIRE WHT/BLU WIRE YEL WIRE

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 GND HI SPD GMLAN SER DATA (+) AUTOMATIC TRANSMISSION ASSEMBLY BCM 1 FUSE BLK WIRE BLK/WHT WIRE BLU WIRE BODY CONTROL MODULE (BCM) (LEFT SIDE OF DASH) COMPUTER DATA LINES SYSTEM CONTROL SOLENOID DK BLU WIRE DRIVER INFORMATION CENTER (DIC) ENGINE CONTROL MODULE (ECM) (LEFT FRONT OF ENGINE COMPT) GMLAN SERIAL DATA BUS + GRN WIRE GRY WIRE GRY/VIO WIRE HDLP SW HDLPS OFF SIG CTRL HI SPD GMLAN SER DATA (-) IGN VOLT HI SPD GMLAN SER DATA (-) WAKEUP SER DATA HI SPD GMLAN SER DATA - HOT AT ALL TIMES HOT AT ALL TIMES UNDERHOOD FUSE BLOCK TCM BATT (LEFT SIDE FUSE OF BATTERY) HOT W/ IGNITION MAIN RELAY ENERGIZED IGN INSTRUMENT CLUSTER INSTRUMENT PANEL FUSE BLOCK (LOWER LEFT SIDE OF DASH) ISS ISS HIGH LOW LOGIC GMLAN LOW REF OSS OSS HIGH LOW P/N PARK/ NEUTRAL SIG GMLAN SERIAL DATA BUS- PC 1 SOLENOID PC 2 SOLENOID PC 3 SOLENOID PC 4 SOLENOID PC 5 SOLENOID POWER DISTRIBUTION SYSTEM PRESSURE CONTROL (PC) SOLENOID VALVE 1 PRESSURE CONTROL (PC) SOLENOID VALVE 2 PRESSURE CONTROL (PC) SOLENOID VALVE 3 PRESSURE CONTROL (PC) SOLENOID VALVE 4 PRESSURE CONTROL (PC) SOLENOID VALVE 5 RAP RELAY COIL CTRL RAP RLY COIL CTRL RED WIRE RED/DK GRN WIRE RED/WHT WIRE SHIFT SOLENOID (SS) VALVE 1 SHIFT SOLENOID (SS) VALVE 2 SS 1 SS 2 TCC SOLENOID TFP 1 TFP 3 TFP 4 TFP 5 TFT TORQUE CONVERTER CLUTCH PRESSURE CONTROL SOLENOID VALVE TRANSMISSION CONTROL MODULE (TCM) TRANSMISSION FLUID PRESSURE SWITCH TRANSMISSION FLUID TEMPERATURE SENSOR TRANSMISSION INPUT SHAFT SPEED SENSOR (ISS) TRANSMISSION INTERNAL MODE SWITCH (IMS) TRANSMISSION MANUAL SHIFT SWITCH TRANSMISSION OUTPUT SHAFT SPEED SENSOR (OSS) TRANSMISSION SHIFT LEVER TRN FSC IGN FUSE TRNS RANGE SIG A TRNS TRNS TRNS GND RANGE RANGE RANGE SIG C SIG B SIG P VALVE ASSEMBLY VIO WIRE VIO/BLK WIRE VIO/YEL WIRE WHT WIRE WHT/GRY WIRE YEL WIRE

BLK WIRE BLU WIRE BLU/YEL WIRE COMPUTER DATA LINES SYSTEM DIFFERENTIAL CLUTCH PUMP (UNDER REAR OF VEHICLE ON DIFFERENTIAL) GMLAN DATA BUS+ GND B+ GMLAN DATA BUS- GMLAN DATA BUS- GND COMMUNICATION ENABLE HOT AT ALL TIMES AWD/ FUSE BLOCK SADS (LEFT SIDE OF FUSE BATTERY) NCA WIRE REAR DIFFERENTIAL CLUTCH CONTROL MODULE (MOUNTED TO REAR DIFFERENTIAL) REAR DIFFERENTIAL CLUTCH SOLENOID VALVE (ON REAR DIFFERENTIAL) REAR DRIVE CLUTCH SOLENOID VALVE RED WIRE RED/BLU WIRE RED/WHT WIRE UNDERHOOD WHT WIRE WHT/BLU WIRE YEL WIRE

20 26 B+ GROUND BATTERY BATTERY CURRENT SENSOR (IN FRONT OF BATTERY) BATTERY FUSE BLOCK (TOP OF BATTERY) BLK WIRE BLK/VIO WIRE BLU/VIO WIRE BODY CONTROL MODULE (LEFT SIDE OF DASH) BRN WIRE CHARGE IND CHARGE IND CTRL COMPUTER DATA LINES SYSTEM CURRENT SENSOR SIG CURRENT SENSOR SUPPLY VOLTAGE DRIVER INFORMATION CENTER DISPLAY ENGINE CONTROL MODULE (LEFT FRONT OF ENGINE COMPT) FUSE 6 GENERATOR GENERATOR FIELD DUTY CYCLE SIG GMLAN SERIAL DATA GRN WIRE GRY WIRE HOT AT ALL TIMES UNDERHOOD FUSE BLOCK (LEFT SIDE OF BATTERY) FUSE 69 INSTRUMENT CLUSTER LOGIC LOW REF RED WIRE RED/YEL WIRE SERIAL DATA STARTER MOTOR VIO/YEL WIRE WHT/YEL WIRE

2.4L AUTOMATIC TRANSMISSION ASSEMBLY AUTOMATIC TRANSMISSION INTERNAL MODE SWITCH BATTERY BATTERY CURRENT SENSOR (IN FRONT OF BATTERY) BATTERY FUSE BLOCK FUSE 5 (TOP OF BATTERY) BLK WIRE BLK/WHT WIRE BLU WIRE BODY CONTROL MODULE (LEFT SIDE OF DASH) CHARGING CIRCUIT COMPUTER DATA LINES SYSTEM CONTROL SOLENOID VALVE ASSEMBLY ENGINE CONTROL MODULE (LEFT FRONT OF ENGINE COMPT) EXCEPT HYBRID HYBRID FUSE 12 FUSE 5 FUSE 6 GMLAN SERIAL DATA GRN WIRE GROUND DISTRIBUTION SYSTEM HOT W/ IGNITION MAIN RELAY ENERGIZED UNDERHOOD FUSE BLOCK (LEFT SIDE OF BATTERY) IGN IGN VOLT IGNITION SWITCH LOCK PARK/NEUTRAL SIG (1) RED WIRE RUN WIRE SERIAL DATA STARTER MOTOR STARTER RELAY STARTER RELAY CTRL TRANSMISSION CONTROL MODULE VIO/GRY WIRE VIO/LT GRN WIRE VIO/YEL WIRE WHT WIRE WHT/GRY WIRE WHT/VIO WIRE YEL WIRE

AIR BAG FUSE AIR BAG IND AIR BAG OFF IND AIR BAG ON IND SEAT BELT ON IND BLK WIRE BLK/ORG WIRE BLU/YEL WIRE BRN WIRE BRN/ORG WIRE COMPUTER DATA LINES SYSTEM DK BLU WIRE FUSE GND SERIAL DATA GRN WIRE GROUND DISTRIBUTION SYSTEM GRY WIRE GRY/BLU WIRE GRY/ORG WIRE HOT AT ALL TIMES HOT W/ IGNITION MAIN RELAY ENERGIZED INFLATABLE RESTRAINT SENSING, DIAGNOSTIC MODULE (BELOW CENTER CONSOLE) INSTRUMENT CLUSTER INSTRUMENT PANEL FUSE BLOCK (LOWER LEFT SIDE OF DASH) LEFT FRONT IMPACT SENSOR (LEFT SIDE OF CROSS MEMBER) LEFT TAILLAMP ASSEMBLY LO SPD GMLAN LOGIC LOW SPD GMLAN SERIAL DATA LOW SPEED GMLAN SERIAL DATA LT GRN WIRE NCA WIRE ORG/ WIRE ORG/GRN WIRE ORG/LT GRN WIRE ORG/VIO WIRE ORG/WHT WIRE ORG/YEL WIRE PASS AIR BAG ON IND PASS AIR BAG OFF IND PASSENGER AIR BAG DISABLED INDICATOR PASSENGER INSTRUMENT PANEL AIR BAG PASSENGER PRESENCE DETECTION MODULE (UNDER FRONT PASSENGER'S SEAT) PNK WIRE PPL RED WIRE RED/WHT WIRE RIGHT FRONT IMPACT SENSOR (RIGHT SIDE OF CROSS MEMBER) SEAT BELT IND SERIAL DATA (-) SERIAL DATA (+) SHORTING BAR STEERING WHEEL AIR BAG STEERING WHEEL AIR BAG COIL TAN WIRE UNDERHOOD FUSE BLOCK (LEFT SIDE OF BATTERY) VIO WIRE VIO/GRY WIRE WHT WIRE WHT/BLU WIRE WHT/GRN WIRE WHT/ORG WIRE YEL WIRE YEL/ORG WIRE

AJAR SW SIG 1 BATT POS VOLT BCM 3 FUSE TRUNK FUSE LEFT SIDE OF DASH) BLK WIRE BODY CONTROL MODULE (BCM) (LEFT SIDE OF DASH) BRN WIRE COMPUTER DATA LINES COMPUTER DATA LINES SYSTEM DK BLU WIRE DK BLU/YEL WIRE EXTERIOR REAR COMPARTMENT LID UNLATCH SWITCH GROUND DISTRIBUTION SYSTEM GRY WIRE GRY/YEL WIRE HANDLE SW OPEN SIG HOT AT ALL TIMES INSTRUMENT CLUSTER INSTRUMENT PANEL FUSE BLOCK (LOWER INTERIOR REAR COMPARTMENT LID UNLATCH SWITCH LOGIC LT GRN WIRE MTR RELEASE CTRL REAR COMPARTMENT LID UNLATCH RELAY RED WIRE RED/WHT WIRE SERIAL DATA SERIAL DATA DRIVER INFORMATION CENTER DISPLAY SYSTEM VIO/GRY WIRE VIO/WHT WIRE WHT WIRE YEL DK BLU/ WIRE YEL WIRE YEL/DK BLU WIRE

AJAR AJAR SW SIG BCM 7 FUSE BLOCK FUSE (LOWER LEFT SIDE OF DASH) BLK WIRE BLK/ORG WIRE BLU WIRE BLU/ WHT WIRE BLU/BLK WIRE BLU/VIO WIRE BODY CONTROL MODULE (LEFT SIDE OF DASH) BRAKE IND BRN WIRE BRN/GRN WIRE BUS 4 COMPUTER DATA LINES SYSTEM DK BLU RED/ WIRE DLIS FUSE DRIVER DOOR LATCH ASSEMBLY DRIVER INFORMATION CENTER DISPLAY DRIVER SEAT BELT BUCKLE DRIVER SEAT BELT SWITCH DRIVER WINDOW MOTOR DRIVER WINDOW SWITCH DRIVER'S DOOR GMLAN SER DATA RADIO GMLAN SERIAL DATA GRN WIRE GRN/GRY WIRE GROUND GRY WIRE GRY/ GRN WIRE GRY/RED WIRE HEAD PARK 5 6 AUTO OFF HEADLAMP SW 22 11 1 PRK LAMP SIG OFF SIG HEADLAMP SWITCH HOT AT ALL TIMES INFLATABLE RESTRAINT SENSING, DIAGNOSTIC MODULE (SDM) (BELOW CENTER CONSOLE) INSTRUMENT CLUSTER INSTRUMENT PANEL LEFT REAR DOOR LATCH ASSEMBLY LEFT REAR WINDOW SWITCH LO SPD GMLAN SER DATA LOGIC LOW ENGINE OIL PRESSURE IND LOW SPD GMLAN SER DATA SER DATA COMMUNICATION ENABLE LOW TIRE PRESSURE IND LT GRN/GRY WIRE LT GRN/YEL WIRE NCA WIRE NETWORK NETWORK BUS 3 NETWORK BUS 4 OFF KEY IGNITION SWITCH IGNITION SWITCH (W/O KEYLESS ENGINE START SWITCH) OFF/RUN/ CRANK VOLT ORG/BRN WIRE PARK BRAKE CONTROL SWITCH (ON PARK BRAKE ASSEMBLY) PARKING BRAKE CONTROL MODULE (BEHIND LEFT REAR WHEEL LINER) PASSENGER DOOR LATCH ASSEMBLY PASSENGER WINDOW MOTOR (FRONT PASSENGER'S DOOR) PRK BRK APPLY SW VOLT REF PRK BRK SW SUP VOLT PRK BRK SW SIG PRK BRK SW SUPP VOLT PRK BRK SW RELEASE SIG PRK BRK SW APPLY SIG RED WIRE RED/DK BLU WIRE RED/LT GRN (OR RED/GRN) WIRE RED/LT GRN WIRE RIGHT REAR DOOR LATCH ASSEMBLY RIGHT REAR WINDOW SWITCH RUN WIRE SEAT BELT IND SEAT BELT SW LOW REF SEAT BELT SW SIG SER DATA LVL COMM SENS ENABLE SIG SERIAL DATA COMM ENABLE SPLICE PACK) (LEFT KICK PANEL) SW SIG VIO WIRE WHT WIRE WHT/BLU WIRE WHT/DK BLU WIRE WHT/YEL WIRE YEL WIRE YEL/RED WIRE

10 13 20 25 WIPER SW LO REF WIPER SW LO SIG WIPER SW HI SIG WASHER SW SIG 16 14 COIL SPLY VOLT WASHER RLY CTRL 23 24 SERIAL DATA (-) SERIAL DATA (+) 2501 2500 COMPUTER DATA LINES SYSTEM BATT POSITIVE VOLT BATTERY FUSE BLOCK (TOP OF BATTERY) BCM 6 FUSE BLK WIRE BODY CONTROL MODULE (LEFT SIDE OF DASH) BRN/GRY WIRE BRN/LT GRN WIRE COMPUTER DATA LINES SYSTEM DELAY SWITCH DK BLU WIRE DRIVER INFORMATION CENTER DISPLAY FRT WIPER FUSE FUSE 5 GRY WIRE GRY/VIO WIRE HOT AT ALL TIMES INSTRUMENT CLUSTER LEFT FRONT STRUT TOWER) LO SPD GMLAN SERIAL DATA LO WASHER FLUID IND CTRL LOGIC LT GRN WIRE MIST OFF PARK SW SIGNAL RED WIRE RED/WHT WIRE UNDERHOOD FUSE BLOCK (LEFT SIDE OF BATTERY) VIO WIRE WASH FRT FUSE WASHER SWITCH WHT WIRE WHT/VIO WIRE WINDSHIELD WASHER FLUID LEVEL IND WINDSHIELD WASHER FLUID LEVEL SWITCH (IN WASHER FLUID RESERVOIR) WINDSHIELD WASHER PUMP (IN WASHER FLUID RESERVOIR) WINDSHIELD WASHER PUMP RELAY WINDSHIELD WIPER MOTOR (LEFT REAR OF ENGINE COMPT) WINDSHIELD WIPER RELAY WINDSHIELD WIPER SPEED CONTROL RELAY WINDSHIELD WIPER/WASHER SWITCH WIPER SW HI SIG WIPER SWITCH YEL WIRE YEL/BRN WIRE