GMC Pickup C3500 (1985-2000) gauges fuse 4 Wiring diagrams

ALL OTHERS BLK (OR RED) WIRE BLK WIRE BRN WIRE CHARGE WARNING INDICATOR FUSIBLE LINK GAUGES FUSE 4 GENERATOR GENERATOR (W/ DUAL GENERATORS) HOT IN RUN, START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) INSTRUMENT CLUSTER LEFT BATTERY MEGA FUSE BLOCK (RIGHT FRONT OF ENGINE COMPT, NEAR BATTERY) NCA WIRE PNK 22 WIRE PNK WIRE POWER DISTRIBUTION SYSTEM RED WIRE RIGHT BATTERY UPLEVEL/ ENHANCED

1-2 SHIFT SOL 1-2 SHIFT SOLENOID 2-3 SHIFT SOL 2-3 SHIFT SOLENOID A/T ISS SENS HI IN A/T ISS SENS IN A/T ISS SENS LO IN A/T ISS SENSOR OUT ACCELERATOR PEDAL POSITION MODULE (PART OF ACCELERATOR PEDAL) APP 1 SIGNAL IN APP 2 SIGNAL IN APP 3 SIGNAL IN AUTOMATIC TRANSMISSION AUTOMATIC TRANSMISSION INPUT SHAFT SPEED SENSOR (LEFT FRONT OF TRANSMISSION) BATTERY IN BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRAKE FUSE 18 BRAKE SWITCH ASSEMBLY (ON BRAKE PEDAL BRACKET) BRAKE SWITCH IN BRN WIRE BRN/WHT WIRE CLASS II DATA DK BLU WIRE DK GRN WIRE ECM-B FUSE ECT SENSOR IN ENGINE COOLANT TEMP SENSOR (NEAR THERMOSTAT HOUSING) FRONT WHEEL LOCK FUEL PUMP, OIL PRESS SWITCH/ SENDER, FUEL PUMP RELAY GAUGES FUSE 4 GROUND GRY WIRE GRY/BLK WIRE HI PPL HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START HOT IN RUN OR START UNDERHOOD FUSE/RELAY CENTER ECM 1 FUSE HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK IGNITION IN INSTRUMENT CLUSTER LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MALFUNCTION INDICATOR LAMP MIL CONTROL ORG/ WIRE PCM GROUND PCS SOL HI OUT PCS SOL LO OUT PNK PNK WIRE PNK WIRE POWER POWERTRAIN CONTROL MODULE (RIGHT SIDE OF DASH NEAR BLOWER MOTOR) PPL PPL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) PPL/WHT WIRE PRESS CTRL SOLENOID LO RED WIRE RED/BLK WIRE SENSOR GROUND STOP/HAZ FUSE 1 STOPLAMP SWITCH IN TAN WIRE TAN/WHT WIRE TCC PWM SOL TCC PWM SOLENOID TFT SENSOR IN TRANS FLUID TEMP SENSOR TRANS FUSE 20 TRANS RANGE "A" TRANS RANGE "B" TRANS RANGE "C" TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANS RANGE SWITCHES TRANSFER CASE CIRCUIT PNK WIRE TRANSFER CASE, AXLE SWITCHES TURN/ HAZARD SWITCH, CHIME MODULE VEHICLE SPEED SENSOR VEHICLE SPEED SENSOR (VSS) ADAPTOR VEHICLE SPEED SENSOR BUFFER (RIGHT SIDE OF DASH) VSS HI IN VSS IN VSS LO IN VSS OUT WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

A/T ACCY AIR BAG ANTI-LOCK BRAKES ANTI-LOCK BRAKES SYSTEM BLK WIRE BLK/WHT WIRE BRAKE PRESSURE WARNING SWITCH (ON REAR OF BRAKE PRESSURE MODULATOR VALVE BODY) BRAKE/ BRN WIRE BRN/WHT WIRE BULB TEST CHECK GAUGES CHECK GAUGES LAMP DRIVER CONVENIENCE CENTER (BEHIND LEFT SIDE OF I/P) DAYTIME RUNNING LAMPS DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ELECTRONIC PRNDL DISPLAY MODULE ENG-I MINI FUSE ENGINE CONTROLS SYSTEM ENGINE CONTROLS SYSTEM SOUND SYSTEMS ENGINE CONTROLS SYSTEM ENGINE COOLANT TEMPERATURE SENDER (FRONT OF LEFT CYLINDER HEAD) FUEL GAUGE FUEL PUMP, SENDER (IN FUEL TANK) GAUGES FUSE 4 GEN WAIT TO GRY WIRE HEADLIGHTS SYSTEM HEADLIGHTS SYSTEM (DRL) HI BEAM HOT IN RUN OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) IGNITION SWITCH ILLUM INSTRUMENT CLUSTER LEFT TURN LOCK OFF W/ DRL ONLY LOW COOLANT LOW COOLANT LEVEL SENDER (IN COOLANT RESERVOIR) LOW ENGINE COOLANT LEVEL INDICATOR MODULE (UNDER CENTER OF I/P) LT BLU WIRE LT GRN WIRE LT GRN/BLK WIRE M/T PNK WIRE NCA WIRE OIL PRESS OIL PRESSURE SWITCH/SENDER (LEFT REAR TOP OF ENGINE) PARK BRAKE WARNING SWITCH (LEFT END OF I/P) PNK WIRE PPL PPL/WHT WIRE RIGHT TURN RUN WIRE SAFETY BELT SERVICE ENGINE SOON SERVICE THROTTLE SOON UP- SHIFT SPEED- OMETER STARTING/CHARGING SYSTEM SUPPLEMENTAL RESTRAINTS SYSTEM TACH VOLT- METER TAN WIRE TAN/ WHT WIRE TAN/BLK WIRE TAN/WHT WIRE TEMP GAUGE TRANS FUSE 20 TRANSMISSSION RANGE SELECTOR TRUNK, TAILGATE, FUEL DOORS SYSTEM TRUNK/TAIL- GATE/FUEL DOORS SYSTEM UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT REAR OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (BEHIND RIGHT END OF I/P) W/O DRL ONLY WARNING SYSTEMS WATER IN FUEL WATER-IN FUEL SENSOR (TOP REAR OF ENGINE) WHT TAN/ WIRE WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

A/T ACCY AIR BAG DAYTIME RUNNING LAMPS ANTI-LOCK BRAKES ANTI-LOCK BRAKES SYSTEM BLK WIRE BLK/ WHT WIRE BLK/WHT WIRE BRAKE PRESSURE WARNING SWITCH (ON REAR OF BRAKE PRESSURE MODULATOR VALVE BODY) BRAKE/ BRN WIRE BRN/WHT WIRE BULB TEST CHECK GAUGES CHECK GAUGES LAMP DRIVER CONVENIENCE CENTER (BEHIND LEFT SIDE OF I/P) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ELECTRONIC PRNDL DISPLAY MODULE ENGINE CONTROLS SYSTEM ENGINE CONTROLS SYSTEM SOUND SYSTEMS ENGINE CONTROLS SYSTEM ENGINE COOLANT TEMPERATURE SENDER (FRONT OF LEFT CYLINDER HEAD) FUEL GAUGE FUEL PUMP OIL PRESSURE SWITCH/SENDER (TOP REAR OF ENGINE) FUEL PUMP, SENDER (IN FUEL TANK) GAUGES FUSE 4 GEN GRY WIRE HEADLIGHTS SYSTEM HEADLIGHTS SYSTEM (DRL) HI BEAM HOT IN RUN OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) IGNITION SWITCH ILLUM INSTRUMENT CLUSTER LEFT TURN LOCK OFF LT BLU WIRE LT GRN WIRE LT GRN/BLK WIRE M/T PNK WIRE NCA WIRE OIL PRESS PARK BRAKE WARNING SWITCH (LEFT END OF I/P) PNK WIRE PPL PPL/WHT WIRE RIGHT TURN RUN WIRE SAFETY BELT SERVICE ENGINE SOON SPEED- OMETER STARTING/CHARGING SYSTEM SYSTEM SUPPLEMENTAL RESTRAINTS TACH VOLT- METER TAN WIRE TAN/ WHT WIRE TAN/BLK WIRE TAN/WHT WIRE TEMP GAUGE TRANS FUSE 20 TRANSMISSION RANGE SELECTOR (LEFT SIDE OF TRANSMISSION) TRUNK, TAILGATE, FUEL DOORS SYSTEM TRUNK/TAIL- GATE/FUEL DOORS SYSTEM UP SHIFT VEHICLE SPEED SENSOR (LEFT REAR OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (BEHIND RIGHT END OF I/P) W/ DRL ONLY W/O DRL ONLY WARNING SYSTEMS WHT TAN/ WIRE WHT WIRE YEL WIRE

AIR BAG FUSE 10 ARMING SENSOR BACKUP LAMP SWITCH BRN WIRE CONVENIENCE CENTER CREWCAB, SUBURBAN, UTILITY ONLY DAYTIME AUDIO RUNNING ALARM LAMPS MODULE RELAY DAYTIME RUNNING LAMPS MODULE DIAGNOSTIC ENERGY RESERVE MODULE ELECTRO- CHROMIC MIRROR FROM IGNITION SWITCH FROM REAR WIPER FUSE GAUGES FUSE 4 HEAD- LAMP/ PANEL DIMMER SWITCH I/P FUSE BLOCK INSTRUMENT CLUSTER LEFT FRONT POWER WINDOW SWITCH LOW ENGINE COOLANT LEVEL MODULE M/T ONLY PNK WIRE PWR WDO CIRCUIT BRKR REAR WINDOW LOCKOUT SWITCH REMOTE KEYLESS ENTRY MODULE RIGHT FRONT POWER WINDOW SWITCH TURN B/U FUSE 16 TURN SIGNAL LAMP FLASHER VEHICLE SPEED SENSOR BUFFER MODULE YEL WIRE

AUDIO ALARM MODULE (ON CONVENIENCE CENTER) BLK WIRE BLK/WHT WIRE DIESEL GAS GAUGES FUSE 4 GRY WIRE HOT AT ALL TIMES HOT IN PARK OR HEADLIGHT HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) ILLUM FUSE 14 INSTRU- MENT CLUSTER SAFETY BELTS INDICATOR KEY-IN WARNING BUZZER SWITCH LEFT DOOR JAMB SWITCH LIGHTS ON INPUT POWER INPUT KEY-IN WARNING LT GRN WIRE ORG/ WIRE PNK IGNITION ON INPUT WIRE PNK WIRE SEAT BELT INPUT GROUND FASTEN BELTS OUT SEAT BELT SWITCH (IN DRIVER'S SAFETY BELT BUCKLE) STOP/HAZ FUSE 1 SUPPLEMENTAL RESTRAINTS SYSTEM TAN WIRE YEL WIRE

4.3L ONLY 423 3 121 PNK WIRE ACCY BLK WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE BULB TEST DISTRIBUTOR (CENTER REAR OF ENGINE) DK BLU WIRE DK GRN/WHT WIRE ENGINE COOLANT TEMPERATURE SENSOR (FRONT OF ENGINE) GAUGES FUSE 4 GRY WIRE HOT AT ALL TIMES HOT IN RUN HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) IGNITION COIL (CENTER REAR OF ENGINE) IGNITION SWITCH INSTRUMENT CLUSTER KNOCK SENSOR (4.3L ONLY) (REAR OF ENGINE) KNOCK SENSOR (RIGHT SIDE OF ENGINE, BELOW EXHAUST MANIFOLD) LINEAR EGR VALVE (4.3L W/ 4L60E, CALIF EMISS. ONLY) (RIGHT SIDE TOP OF ENGINE) LOCK OFF LT BLU/WHT WIRE LT GRN WIRE MANIFOLD ABSOLUTE PRESSURE SENSOR (RIGHT REAR TOP OF ENGINE) NCA WIRE ORG/ WIRE PNK WIRE PPL PPL 1 2 3 4 PPL 23 24 PPL/WHT WIRE RED WIRE RED/BLK WIRE RUN WIRE SERVICE ENGINE SOON INDICATOR TACHOMETER TEST LEAD TAN WIRE TAN/BLK WIRE TCC/BRAKE SWITCH (TOP OF BRAKE PEDAL BRACKET) THROTTLE POSITION SENSOR (RIGHT SIDE OF THROTTLE BODY) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

413 412 PPL AIR CONDITIONING SYSTEM (A/C COMPRESSOR CLUTCH) BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE CRANK SIGNAL COOLANT TEMP SENS SIG MAP SENSOR SIGNAL DATA LINK CONNECTOR (UNDER LEFT SIDE OF I/P) DISTRIBUTOR REF HI DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-B MINI FUSE ECM-I MINI FUSE EGR SOLENOID MIL INDICATOR CTRL ENG-I MINI FUSE FUEL PUMP RELAY CTRL FUEL PUMP SIGNAL INPUT DISTRIBUTOR REF LO GAUGES FUSE 4 GRY WIRE HOT AT ALL TIMES HOT IN RUN OR START HOT IN RUN, BULB TEST OR START HOT IN START I/P FUSE BLOCK CRANK FUSE 8 IAC COIL B LO IAC COIL B HI IAC COIL A HI IAC COIL A LO IDLE AIR CONTROL UNIT (RIGHT REAR OF TBI UNIT) IGN E MINI FUSE IGNITION CONTROL (IC) IC BYPASS OXYGEN SENSOR GROUND OXYGEN SENSOR SIGNAL INJECTOR 1 DRIVER INJECTOR 2 DRIVER INSTRUMENT CLUSTER LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE NCA WIRE ORG/ WIRE OXYGEN SENSOR (RIGHT SIDE EXHAUST MANIFOLD) PNK 21 22 WIRE PNK WIRE POWERTRAIN CONTROL MODULE (UNDER RIGHT SIDE OF I/P) PPL PPL/WHT WIRE RED/BLK WIRE SERVICE ENGINE SOON INDICATOR SPARK RETARD SIGNAL A/C ON SIGNAL IN SYSTEM GROUND SYSTEM GROUND SENSOR RETURN GROUND TAN WIRE TAN/BLK WIRE THROTTLE BODY FUEL INJECTOR #1 (TOP OF THROTTLE BODY UNIT) THROTTLE BODY FUEL INJECTOR #2 (TOP OF THROTTLE BODY UNIT) TP SENSOR SIGNAL UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) UP- SHIFT LAMP UPSHIFT LAMP CTRL DLC SERIAL DATA DLC DIAGNOSTIC TEST VSS BUFFER SIGNAL WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

423 3 121 PNK WIRE ACCY BLK WIRE BRN WIRE BRN/WHT WIRE BULB TEST DISTRIBUTOR (CENTER REAR OF ENGINE) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ENGINE COOLANT TEMPERATURE SENSOR (RIGHT TOP FRONT OF ENGINE) GAUGES FUSE 4 GRY WIRE HOT AT ALL TIMES HOT IN RUN OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) IGNITION COIL (CENTER REAR OF ENGINE) IGNITION SWITCH INSTRUMENT CLUSTER KNOCK SENSOR (REAR OF LEFT CYLINDER HEAD) LOCK OFF LT BLU/WHT WIRE LT GRN WIRE MANIFOLD ABSOLUTE PRESSURE SENSOR (REAR TOP CENTER OF ENGINE) NCA WIRE ORG/ WIRE PNK PNK PNK 25 26 27 WIRE PNK WIRE PNK/BLK WIRE PPL PPL 1 2 3 4 PPL 22 23 PPL/WHT WIRE RED WIRE RED/BLK WIRE RUN WIRE SERVICE ENGINE SOON INDICATOR TACHOMETER TEST LEAD TAN WIRE TAN/BLK WIRE TCC/BRAKE SWITCH (TOP OF BRAKE PEDAL BRACKET) THROTTLE POSITION SENSOR (RIGHT SIDE OF THROTTLE BODY) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

4.3L ONLY 423 3 121 PNK WIRE ACCY BLK WIRE BRN WIRE BRN/WHT WIRE BULB TEST DISTRIBUTOR (CENTER REAR OF ENGINE) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ENGINE COOLANT TEMPERATURE SENSOR (FRONT OF ENGINE) GAUGES FUSE 4 GRY WIRE HOT AT ALL TIMES HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) IGNITION COIL (CENTER REAR OF ENGINE) IGNITION SWITCH INSTRUMENT CLUSTER KNOCK SENSOR (4.3L ONLY) (REAR OF ENGINE) KNOCK SENSOR (RIGHT SIDE OF ENGINE, BELOW EXHAUST MANIFOLD) LINEAR EGR VALVE (7.4L ONLY) (RIGHT SIDE TOP OF ENGINE) LOCK OFF LT GRN WIRE MANIFOLD ABSOLUTE PRESSURE SENSOR (RIGHT REAR TOP OF ENGINE) NCA WIRE ORG/ WIRE PNK WIRE PPL PPL 1 2 3 4 PPL/WHT WIRE RED/BLK WIRE RUN WIRE SERVICE ENGINE SOON INDICATOR TACHOMETER TEST LEAD TAN WIRE TAN/BLK WIRE THROTTLE POSITION SENSOR (RIGHT SIDE OF THROTTLE BODY) UPSHIFT LAMP WHT WIRE WHT/BLK WIRE YEL WIRE