Buick LaCrosse I (2004-2009) (on transmission stud, to right of starter) Wiring diagrams

12 13 14 15 16 PPL 8 1450 734 720 INTERIOR LIGHTS SYSTEM A/C CLU DIODE A/C CLUTCH FUSE 13 A/C COMP RELAY 38 AUTO OFF BLOWER MOTOR SW BATTERY IGN 1 VOLT CLASS 2 SERIAL BLK WIRE BLK/WHT WIRE BRN WIRE COMPUTER DATA LINES SYSTEM DEFOGGER IND DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE FAN 1 FUSE 29 FAN 1 RELAY 42 FAN 2 FUSE 32 FAN 2 RELAY 46 FAN 3 RELAY 43 GROUND GRY WIRE GRY/BLK WIRE HIGH LOW HOT AT ALL TIMES HOT IN RUN OR START HVAC CONTROL MODULE (CENTER OF DASH) ILLUM LOGIC LOWER LEFT AIR TEMPERATURE SENSOR (BEHIND HVAC CONTROL MODULE) LOWER RIGHT AIR TEMPERATURE SENSOR (BEHIND HVAC CONTROL MODULE) LT BLU WIRE LT BLU/BLK WIRE LT GRN WIRE LT GRN/BLK WIRE MODE ACTUATOR (LOWER LEFT SIDE OF HVAC ASSEMBLY) MODE SWITCH ORG/ WIRE ORG/BLK WIRE PNK WIRE PNK/WHT WIRE REAR DEFOGGER SWITCH RECIRCULATION ACTUATOR (NEAR RIGHT "A" PILLAR, ON UPPER HVAC CASE) RECIRCULATION IND RECIRCULATION SWITCH REQUEST SWITCH A/C A/C REQUEST IND SENSOR SIG SENSOR SIG LOW REF SENSOR SIG LOW REF SENSOR SIG LOW REF SENSOR SIG LOW REF SENSOR SIG SENSOR SIG LOW REF PPL SPEED CTRL TAN WIRE TAN/BLK WIRE TAN/WHT WIRE TEMPERATURE CONTROL SW UNDERHOOD FUSE BLOCK (MOUNTED TO RIGHT STRUT TOWER) WHT WIRE WHT/BLK WIRE YEL WIRE

31 4 7 15 33 A/C PRESS SIGNAL A/C CLU DIODE A/C CLUTCH FUSE 13 A/C COMP RELAY A/C REFRIGERANT PRESSURE SENSOR (ON LEFT SIDE OF ENGINE COMPT, ON ACCUMULATOR) A/C REQUEST IND A/C REQUEST SWITCH AUTOMATIC A/C BATTERY IGNITION 1 BLK WIRE BLK/WHT WIRE CLASS 2 SERIAL COMPUTER DATA LINES SYSTEM DISPLAY FUSE 18 DK GRN WIRE DK GRN/WHT WIRE GROUND GRY WIRE HARNESS, APPROXI- MATELY 20 CM FROM HOT AT ALL TIMES HOT AT ALL TIMES I/P FUSE BLOCK HVAC FUSE (BEHIND RIGHT SIDE OF DASH) HOT IN RUN OR START HVAC CONTROL MODULE (CENTER OF DASH) LOGIC LOW REF CLASS 2 SERIAL A/C COMP CLUTCH MANUAL A/C ORG/ WIRE PNK WIRE POWERTRAIN CONTROL MODULE (PCM) RED/BLK WIRE TOWARDS BRAKE PEDAL POSITION SENSOR) UNDERHOOD FUSE BLOCK (MOUNTED TO RIGHT STRUT TOWER) WHT WIRE

380 2700 2751 473 335 1049 31 4 7 50 48 15 33 A/C PRESS SIGNAL 55 29 410 2761 ECT SENS SIG LOW REF A/C CLU DIODE A/C CLUTCH FUSE 13 A/C COMP RELAY A/C REFRIGERANT PRESSURE SENSOR (ON LEFT SIDE OF ENGINE COMPT, ON ACCUMULATOR) A/C REQUEST IND A/C REQUEST SWITCH AIR TEMP B AIR TEMP A RECIRCULATION B RECIRCULATION A AIR TEMPERATURE ACTUATOR (RIGHT SIDE OF HVAC ASSEMBLY) BATT MAIN 4 FUSE 30 BATTERY IGNITION 1 BLK WIRE BLK/WHT WIRE BLOWER MOTOR (BEHIND RIGHT SIDE OF DASH, IN HVAC MODULE) BLOWER MOTOR CONTROL PROCESSOR (ON LOWER RIGHT SIDE OF DASH) BREAKOUT TO DATA LINK CONNECTOR TOWARDS BRAKE PEDAL POSITION SENSOR) CLASS 2 SERIAL COMPUTER DATA LINES SYSTEM DEFOGGER IND REAR DEFOGGER SWITCH DISPLAY FUSE 18 DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ENGINE COOLANT TEMPERATURE (ECT) SENSOR (ON TOP RIGHT OF INTAKE MANIFOLD) FAN 1 FUSE 29 FAN 1 RELAY 42 FAN 2 FUSE 32 FAN 2 RELAY 46 FAN 3 RELAY 43 GROUND GRY WIRE GRY/BLK WIRE HARNESS, APPROXI- MATELY 20 CM FROM HIGH LOW HOT AT ALL TIMES HOT AT ALL TIMES I/P FUSE BLOCK HVAC FUSE (BEHIND RIGHT SIDE OF DASH) HOT IN RUN OR START HVAC CONTROL MODULE (CENTER OF DASH) ILLUM ILLUM INTERIOR 8 1450 LIGHTS SYSTEM LEFT COOLING FAN MOTOR (ON LEFT SIDE OF RADIATOR) LOGIC LOW REF HIGH SPD COOLING LOW SPD COOLING CLASS 2 SERIAL A/C COMP CLUTCH LT BLU WIRE LT GRN WIRE LT GRN/BLK WIRE MODE ACTUATOR (LOWER LEFT SIDE OF HVAC ASSEMBLY) MODE SWITCH OFF BLOWER MOTOR SW ORG/ WIRE PNK WIRE PNK/WHT WIRE PPL PPL SUPPLY GND BATTERY SPEED CTRL GND RECIRCULATION ACTUATOR (NEAR RIGHT "A" PILLAR, ON UPPER HVAC CASE) RECIRCULATION IND RECIRCULATION SWITCH RED WIRE RED/BLK WIRE RIGHT COOLING FAN MOTOR (ON RIGHT SIDE OF RADIATOR) RIGHT STRUT TOWER) SPEED CTRL MODE DOOR B MODE DOOR A TAN WIRE TEMPERATURE CONTROL SW TOWARDS BRAKE PEDAL POSITION SENSOR) UNDERHOOD FUSE BLOCK (MOUNTED TO WHT WIRE YEL WIRE

3.6L 3.8L A/C CLU DIODE A/C COMPRESSOR CLUTCH A/C WIPER RELAY 37 RELAY 45 AUTOMATIC TRANSMISSION TRANSMISSION CLUTCH INTERNAL MODE DIODE SWITCH (IMS) BATTERY BLK WIRE BODY CONTROL MODULE (BCM) ELECTRONIC BRAKE CONTROL MODULE (EBCM) EXCEPT SULEV FUEL PP RELAY 41 HEADLAMP ASSEMBLY) HOOD AJAR SWITCH HORN ASSEMBLY IGN 1 HDM BEAM MODULE 35 IGN 1 HDM BEAM RELAY 37 MODULE 35 LAMP LEFT FRONT MARKER LAMP LEFT HIGH BEAM HEADLAMP POWERTRAIN CONTROL MODULE (PCM) RIGHT COOLING FAN RIGHT FRONT MARKER LAMP RIGHT FRONT PARK/ RIGHT TURN FRONT SIGNAL FOG LAMP LAMP RIGHT HIGH BEAM HEADLAMP SECONDARY AIR INJECTION (AIR) PUMP (SULEV) SULEV TAN WIRE THROTTLE ACTUATOR CONTROL (TAC) MODULE TRANSMISSION CONTROL MODULE (TCM) FUEL PP RELAY 41 WHT WIRE WINDSHIELD WASHER FLUID LEVEL SWITCH WINDSHIELD WASHER FLUID PUMP

1-2 SHIFT SOLENOID 2-3 SHIFT SOLENOID A/T FLUID TEMP SENSOR AIR PRES SENS AT ISS SIG AUTOMATIC TRANSMISSION PRESSURE CONTROL SOLENOID BLK WIRE BLK/WHT WIRE BOOST SOL BRN WIRE DK BLU/WHT WIRE DK GRN WIRE GRY WIRE IAT SENSOR SIG INPUT SHAFT SPEED SENSOR LOW REF LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE MAF SENSOR SIG NEAR AIR CLEANER ASSEMBLY) ORG/ WIRE PC SOL PNK PNK WIRE PNK WIRE POWERTRAIN CONTROL MODULE (LEFT SIDE OF ENGINE COMPARTMENT) PPL RED WIRE RED/BLK WIRE SHIFT SOL TAN WIRE TAN/BLK WIRE TAN/WHT WIRE TCC RELEASE SWITCH TCC SOL TCC SW SIG TFT SENSOR SIG TORQUE CONVERTER CLUTCH SOLENOID TR SW A TR SW B TR SW C TR SW P TRANSMISSION INTERNAL MODE SWITCH VEHICLE SPEED SENSOR (RIGHT SIDE OF TRANSMISSION, NEAR RIGHT AXLE SHAFT) VSS SIG WHT WIRE YEL WIRE YEL/BLK WIRE