Chevrolet Impala VIII (1999-2006) underhood junction block (top) (on front of right strut tower) Wiring diagrams

BLK WIRE BLK/WHT WIRE BODY CONTROL MODULE (BEHIND LEFT SIDE OF DASH, ABOVE PARKING BRAKE LEVER) BRN WIRE DIC/ RKE FUSE DRIVER INFORMATION CENTER EMERGENCY VEHICLE REAR COMPARTMENT LID LAMPS RELAY HOT AT ALL TIMES LEFT EMERGENCY VEHICLE REAR COMPARTMENT LID LAMP LEFT SPOT LAMP LEFT SPOT LMP FUSE NCA WIRE ORG/ WIRE REAR COMPARTMENT LID AJAR SWITCH RED/BLK WIRE RIGHT EMERGENCY VEHICLE REAR COMPARTMENT LID LAMP RIGHT I/P JUNCTION BLOCK (RIGHT SIDE OF DASH, BEHIND ACCESS PANEL) RIGHT SPOT LAMP RIGHT SPOT LMP FUSE TAN WIRE UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER) W/ DRIVER INFORMATION DISPLAY CENTER W/ REAR COMPT LID EMERGENCY LAMP PACKAGE YEL WIRE

A/C RLY (CMPR) FUSE BATTERY BLK WIRE CLASS 2 SERIAL DATA DATA LINK CONNECTOR (BELOW LEFT SIDE OF DASH, RIGHT OF STEERING COLUMN) PPL DK GRN WIRE FUSIBLE LINK (10 GA- RUST) (FRONT OF ENGINE, ON STARTER SOLENOID) GENERATOR GENERATOR TURN ON SIGNAL GRN WIRE GRY WIRE HOT AT ALL TIMES HOT IN ON OR START IGN VOLT INSTRUMENT PANEL CLUSTER (IPC) IPC CLASS 2 SERIAL DATA LEFT I/P JUNCTION BLOCK (LEFT SIDE OF DASH, BEHIND ACCESS PANEL) LOGIC MESSAGE CENTER CHARGE IND ORG/ WIRE PCM/BCM/CLSTR FUSE POWER DISTRIBUTION SYSTEM POWERTRAIN CONTROL MODULE (PCM) (IN AIR CLEANER BOX) PPL RED WIRE STARTER SOLENOID UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER)

39 27 34 COMP CONTROL A/C PRESS SIGNAL 80 59 LOW REFERENCE SERIAL DATA A/C CMPR RELAY A/C COMPRESSOR CLUTCH A/C COMPRESSOR CLUTCH DIODE (LOWER LEFT SIDE OF ENGINE, AT A/C COMPRESSOR) A/C REFRIGERANT PRESSURE SENSOR (ON LEFT SIDE OF ENGINE COMPT, ON LIQUID LINE) A/C RLY (CMPR) FUSE A/C RLY (COIL) FUSE BLK WIRE COMPUTER DATA LINES SYSTEM DK GRN WIRE DK GRN/WHT WIRE GRY WIRE HOT AT ALL TIMES HOT IN RUN NCA WIRE ORG/ WIRE PNK WIRE POWER DISTRIBUTION SYSTEM POWERTRAIN CONTROL MODULE (PCM) (IN AIR CLEANER BOX) RED/BLK WIRE UNDERHOOD JUNCTION BLOCK (BOTTOM) (ON FRONT OF RIGHT STRUT TOWER) UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER)

AC HEADLAMP RELAY AMBIENT LIGHT SENSOR (TOP RIGHT OF DASH, NEAR DEFOGGER OUTLET) BLK WIRE BLK/WHT WIRE BLOCK (LEFT SIDE OF DASH, BEHIND ACCESS PANEL) BODY CONTROL MODULE (BCM) (BEHIND LEFT SIDE OF DASH, ABOVE PARKING BRAKE LEVER) BRN WIRE COMPUTER DATA LINES SYSTEM DK BLU WIRE DK GRN/WHT WIRE DRL RELAY DRL RELAY SERIAL DATA FOG LP RELAY HIGH BEAM IN HEADLAMP RLY DRL/EXT LTS FUSE EXT LTS FUSE FOG LAMP INDICATOR FOG LAMP SWITCH FOG LIGHT RELAY FOG LP SW PARK BRAKE IN GROUND DISTRIBUTION SYSTEM GRY WIRE HEAD HEADLAMP DIMMER SWITCH HEADLAMP SW AL SENS SIG AL SENS REF 1138 1137 HEADLAMP SWITCH HIGH BEAM HIGH BEAM IND HIGH BEAM OUT HOT AT ALL TIMES IPC CLASS 2 SERIAL DATA LEFT FRONT FOG LAMP LEFT HEADLAMP LEFT I/P JUNCTION LEFT I/P JUNCTION BLOCK (LEFT SIDE OF DASH, BEHIND ACCESS PANEL) LOGIC INSTRUMENT PANEL CLUSTER (IPC) LOW BEAM LT BLU WIRE LT GRN WIRE LT GRN/BLK WIRE MESSAGE CENTER OFF ORG/ WIRE PARK PARK BRAKE SWITCH (AT BASE OF PARKING BRAKE ASSEMBLY) PNK PNK WIRE PNK WIRE PPL RIGHT FRONT FOG LAMP RIGHT HEADLAMP LOW BEAM TURN SIGNAL/ MULTIFUNCTION SWITCH UNDERHOOD JUNCTION BLOCK (TOP) UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER) UNDERHOOD JUNCTION BLOCK (TOP) FOG RLY FUSE YEL WIRE YEL/BLK WIRE

BLK WIRE DK GRN WIRE HORN ASSEMBLY (LOWER RIGHT FRONT OF VEHICLE) HORN RELAY HORN RELAY FUSE HORN SWITCH HOT AT ALL TIMES NCA WIRE ORG/ WIRE SLIP RING SPRING STEERING COLUMN HORN BRUSH UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER)

BLK WIRE BLK/WHT WIRE BODY CONTROL MODULE (BEHIND LEFT SIDE OF DASH, ABOVE PARKING BRAKE LEVER) BRN WIRE FULL BRIGHT GRY WIRE GRY/BLK WIRE HEAD PARK LAMP SWITCH HEADLAMP SWITCH HOT AT ALL TIMES I/P DIMMING SWITCH INT DIM CTRL RELAY CTRL GROUND GROUND GROUND LEFT CRUISE CONTROL (SET/ COAST) LEFT I/P JUNCTION BLOCK (LEFT SIDE OF DASH, BEHIND ACCESS PANEL) LEFT RADIO CONTROL (SEEK/ PRESET) LOW DIM LT BLU WIRE NCA WIRE OFF PARK PARK LAMP RELAY PARK LAMP SWITCH INPUT REAR PARK LMP FUSE RED WIRE RIGHT CRUISE CONTROL (RESUME/ ACCEL) RIGHT I/P 1 FUSE RIGHT I/P JUNCTION BLOCK (RIGHT SIDE OF DASH, BEHIND ACCESS PANEL) RIGHT RADIO CONTROL (VOLUME/ MODE) STEERING COLUMN FUSE STEERING WHEEL) TO HVAC CONTROL MODULE (DIAGRAM 2 OF 2) TO LEFT I/P JUNCTION BLOCK (DIAGRAM 2 OF 2) UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER) WHT WIRE

39 26 27 34 COMP CONTROL ECT SIGNAL A/C PRESS SIGNAL 59 5 6 13 80 CLASS 2 SERIAL HIGH SPEED LOW SPEED ECT GROUND LOW REFERENCE A/C CMPR RELAY A/C COMPRESSOR CLUTCH A/C REFRIGERANT PRESSURE SENSOR (ON LEFT SIDE OF ENGINE COMPT, ON LIQUID LINE) A/C REQUEST IND A/C REQUEST SIG A/C REQUEST SWITCH A/C RLY (CMPR) FUSE A/C RLY (COIL) FUSE BATTERY POSITIVE BLK WIRE BLK/WHT WIRE BLOWER MOTOR BLOWER MOTOR (ON RIGHT BOTTOM OF HEATER-A/C ASSEMBLY) BLOWER MOTOR CONTROL PROCESSOR (LOWER RIGHT SIDE OF DASH) BODY CONTROL MODULE (BEHIND LEFT SIDE OF DASH, ABOVE PARKING BRAKE LEVER) BREAKOUT) BREAKOUT) (3.8L (VIN K): LEFT REAR OF ENGINE, 6.5 CM FROM EGR VALVE BREAKOUT) BRN WIRE COMPUTER DATA LINES SYSTEM D TEMP CONTROL SWITCH DEFOG SWITCH DEFOGGER SYSTEM COMPUTER DATA LINES SYSTEM DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DR CTRL A DR CTRL B DR CTRL A DR CTRL B DOOR CTRL A DOOR CTRL B ENGINE CONTROLS SYSTEM ENGINE COOLANT TEMPERATURE FAN CONT 1 FUSE FAN CONT 1 RELAY FAN CONT 2 RELAY FAN CONT 2, 3 FUSE FAN CONT 3 RELAY GROUND GRY WIRE GRY/BLK WIRE HOT AT ALL TIMES HOT IN ON HVAC BLOWER FUSE HVAC CLASS 2 SERIAL DATA HVAC CLASS 2 SERIAL DATA BATTERY ILLUM LEFT AIR TEMPERATURE ACTUATOR (ON LEFT SIDE OF HEATER- A/C ASSEMBLY) LEFT COOLING FAN (FRONT OF ENGINE COMPT) LT BLU WIRE LT GRN WIRE LT GRN/BLK WIRE MODE ACTUATOR (LOWER RIGHT SIDE OF DASH) MODE SWITCH NCA WIRE ORG/ WIRE ORG/BLK WIRE OUT SIDE AIR IND OUT SIDE AIR SWITCH P TEMP CONTROL SWITCH PNK IGN 3 VOLT GROUND WIRE PNK WIRE PNK/WHT WIRE POWER DISTRIBUTION SYSTEM PPL REAR DEFOG RLY CTRL RECIRCULATION ACTUATOR RECIRCULATION IND RECIRCULATION SWITCH RED WIRE RED/BLK WIRE RIGHT AIR TEMPERATURE ACTUATOR (ON RIGHT SIDE OF HEATER- A/C ASSEMBLY) RIGHT COOLING FAN (FRONT OF ENGINE COMPT) S121 (3.4L (VIN E)) (FUEL INJECTOR JUMPER SPEED CTRL SPEED CTRL DOOR CTRL POSITION SIG STARTER SUPPLY VOLTAGE TAN WIRE UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER) VOLTAGE WHT WIRE WHT/BLK WIRE YEL WIRE

AUDIO AMPLIFIER (W/ PERFORMANCE ENHANCED SPEAKER) BATTERY BLK WIRE BLK/WHT WIRE BLOWER MOTOR CONTROL PROCESSOR BLUNT CUT WIRE AT RIGHT FRONT FLOOR BREAKOUT) CIRCUIT BREAKER 1 CIRCUIT BREAKER 2 CIRCUIT BREAKER 3 COOLING FANS FUSE CRANK RLY RELAY DK GRN WIRE DRIVER OUTSIDE REARVIEW MIRROR DIGITAL RADIO RECEIVER (W/ DIGITAL RADIO) ELECTRONIC BRAKE CONTROL MODULE (EBCM) FROM CRANK RELAY (DIAGRAM 2 OF 5) FROM RIGHT I/P 3 FUSE (DIAGRAM 1 OF 5) FUSE BLOCK (SEO) (BEHIND DASH, RIGHT OF STEERING COLUMN) FUSIBLE LINK FUSIBLE LINK (10 GA-RUST) FUSIBLE LINK FUSIBLE LINK GENERATOR HTD MIR FUSE HVAC BLOWER FUSE IGN RLY RELAY IGN SW FUSE LEFT I/P FUSE LEFT I/P JUNCTION BLOCK (LEFT SIDE OF DASH, BEHIND ACCESS PANEL) NCA WIRE ORG/ WIRE PASSENGER OUTSIDE REARVIEW MIRROR PNK WIRE RADIO RADIO ANTENNA MODULE RADIO FUSE REAR BRKR DEFOG CIRCUIT BREAKER REAR DEFOG RELAY REAR JUNCTION BLOCK (BEHIND RIGHT REAR WHEELWELL) RED WIRE RIGHT I/P 1 FUSE RIGHT I/P 2 FUSE RIGHT I/P 3 FUSE SEO RELAY SEO RELAY STARTER TO FAN CONT 1 FUSE (DIAGRAM 3 OF 5) TO IGNITION SWITCH (DIAGRAM 2 OF 5) TO LEFT I/P JUNCTION BLOCK (DIAGRAM 3 OF 5) TO REAR DEFOG RELAY (DIAGRAM 1 OF 5) TO RIGHT I/P JUNCTION BLOCK (DIAGRAM 4 OF 5) TO RIGHT I/P JUNCTION BLOCK (DIAGRAM 5 OF 5) TO UNDERHOOD JUNCTION BLOCK (BOTTOM) (DIAGRAM 3 OF 5) TO UNDERHOOD JUNCTION BLOCK (TOP) (DIAGRAM 5 OF 5) U/HOOD 1 FUSE U/HOOD 2 FUSE UNDERHOOD JUNCTION BLOCK (TOP) UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER) W/ SEO

A/C-CRUISE FUSE ABS/PCM FUSE BCM FUSE STOP FUSE BLK WIRE BLUNT CUT WIRE AT RIGHT FRONT FLOOR (W/ SEO) BODY CONTROL MODULE (BCM) BODY CONTROL MODULE (BCM) PNK WIRE BRN WIRE CIG/ AUX FUSE CRANK RELAY CRUISE CONTROL MODULE (CCM) CRUISE CONTROL ON/OFF SWITCH CRUISE CONTROL RELEASE SWITCH CRUISE FUSE DK BLU WIRE DK GRN WIRE DRIVER INFORMATION CENTER (DIC) ELECTRONIC BRAKE CONTROL MODULE (EBCM) POWERTRAIN CONTROL MODULE (PCM) EVAPORATIVE EMISSIONS (EVAP) CANISTER VENT SOLENOID FROM IGN SW FUSE (DIAGRAM 1 OF 5) FROM IGNITION SWITCH (DIAGRAM 2 OF 5) HAZARD SWITCH HVAC CONTROL MODULE IGNITION KEY ALARM SWITCH (CLOSED WITH KEY IN IGNITION SWITCH) IGNITION SWITCH INFLATABLE RESTRAINT SENSING, DIAGNOSTIC MODULE (SDM) INSIDE REARVIEW MIRROR INSTRUMENT PANEL CLUSTER (IPC) JUNCTION BLOCK LEFT I/P JUNCTION BLOCK (LEFT SIDE OF DASH, BEHIND ACCESS PANEL) LT GRN WIRE NCA WIRE ON LOCK OFF ORG/ WIRE PCM (CRANK) FUSE PCM/BCM CLSTR FUSE PNK PNK WIRE PNK WIRE POWERTRAIN CONTROL MODULE (PCM) POWERTRAIN CONTROL MODULE (PCM) PPL PPL PPL PPL RED WIRE SRS FUSE STOP LAMP SWITCH TO AUXILIARY POWER DROP CONNECTOR (DIAGRAM 5 OF 5) TO CRUISE FUSE (DIAGRAM 2 OF 5) TO IGNITION RELAY (DIAGRAM 1 OF 5) TO PCM (CRANK) FUSE (DIAGRAM 2 OF 5) TO PCM/BCM/ CLSTR FUSE (DIAGRAM 2 OF 5) TURN SIGNAL FUSE UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER) W/ ABS W/ DISPLAY DRIVER INFORMATION CENTER W/ GPS W/O GPS WARNING SYSTEM WHT WIRE WINDSHIELD WIPER SYSTEM MODULE WINDSHIELD WIPER/ WASHER SWITCH WSW FUSE YEL WIRE

ABS/PCM FUSE BATTERY BLK WIRE BLU WIRE CLASS 2 SERIAL DATA CRANK RELAY DK GRN WIRE FUSIBLE LINK (10 GA- RUST) (FRONT OF ENGINE, ON STARTER SOLENOID) FUSIBLE LINK (18 GA- GENERATOR HOLD- IN COIL PULL- IN COIL HOT AT ALL TIMES HOT IN ON OR START IGNITION SWITCH LEFT I/P JUNCTION BLOCK (LEFT SIDE OF DASH, BEHIND ACCESS PANEL) ON LOCK OFF PCM (CRANK) FUSE PNK WIRE POWER DISTRIBUTION SYSTEM POWERTRAIN CONTROL MODULE (PCM) (IN AIR CLEANER BOX) PPL PPL CRANK REQUEST CRANK RELAY CTRL RED WIRE STARTER MOTOR STARTER SOLENOID UNDERHOOD JUNCTION BLOCK (TOP) (ON FRONT OF RIGHT STRUT TOWER) YEL WIRE YEL/BLK WIRE