GMC Forward Control P3500 (1985-1999) tan/wht Wiring diagrams

1-3 FUSE 9 12 2 DATA LINK CONNECTOR (BELOW DASH, NEAR STEERING COLUMN) PPL ABS IND. BATTERY GROUND BLK (OR BLK/WHT) WIRE BLK WIRE BRAKE IND BRAKE PRESSURE DIFFERENTIAL SWITCH (INTERNAL TO ELECTRONIC BRAKE CONTROL MODULE) BRN WIRE DIESEL DIESEL: ENGINE HARN, 32 CM FROM BREAKOUT TO BATTERY JUNCTION BLOCK) DIODE NETWORK (ON I/P HARNESS, BODY BUILDER INSTALLED) DK GRN WIRE ELECTRONIC BRAKE CONTROL MODULE (BELOW RADIATOR, ON LOWER CROSSMEMBER) FUSE LINK (IN BATTERY JUNCTION BLOCK, AT LEFT REAR OF ENGINE COMPT) GAS GAS DIESEL GAUGES FUSE 8 HOT AT ALL TIMES HOT IN RUN HOT IN RUN AND START I/P FUSE BLOCK (BEHIND DASH PANEL) (BODY BUILDER INSTALLED) IGNITION ABS LAMP CONTROL BRAKE SW INPUT INSTRUMENT CLUSTER LEFT FRONT WHEEL SPEED SENSOR LT BLU WIRE LT GRN WIRE NCA WIRE PNK WIRE PPL PPL PPL 1807 680 RED WIRE RIGHT FRONT WHEEL SPEED SENSOR SENSOR LOW SENSOR LOW SENSOR HIGH SENSOR HIGH 873 833 STOPLAMPS SWITCH (AT BRAKE PEDAL SUPPORT) TAN WIRE TAN/WHT WIRE VEHICLE SPEED SENSOR CALIBRATOR (LEFT SIDE OF DRIVER'S ISLAND ON RELAY BRACKET) WARNINGS SYSTEM YEL WIRE YEL/BLK WIRE

ABS IND. BLK WIRE BLK/ WHT WIRE BRAKE IND BRAKE PRESSURE DIFFERENTIAL SWITCH BRAKE/ BRN WIRE DIESEL GASOLINE DK GRN WIRE ELECTRONIC BRAKE CONTROL MODULE (BELOW RADIATOR OF FIRST CROSSMEMBER) FUSIBLE LINK HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START GAUGES FUSE I-3 FUSE I/P FUSE BLOCK IGN ABS LAMP CONTROL BRAKE SW INPUT INSTRUMENT CLUSTER LEFT FRONT WHEEL SPEED SENSOR LFT FRT SENSOR (-) LT BLU WIRE LT GRN WIRE PNK WIRE PPL PPL PPL PUMP MOTOR POWER PUMP MOTOR GROUND RED WIRE RIGHT FRONT WHEEL SPEED SENSOR RT FRT SENSOR (-) LFT FRT SENSOR (+) RT FRT SENSOR (+) TAN WIRE TAN/WHT WIRE TCC/ STOPLAMP SWITCH UNDERHOOD FUSE-RELAY CENTER VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED SIG VSS BUFFER (LEFT SIDE OF INTERIOR BULKHEAD) VSS SIG SERIAL DATA LINE SERIAL DATA SIGNAL BRAKE LAMP CONTROL EBCM GROUND WHT WIRE YEL WIRE YEL/BLK WIRE

1996 VFTC ACCY BLK WIRE BLK/WHT WIRE BULB TEST DAYTIME RUNNING LAMPS (DRL) MODULE (ATTACHED TO I/P HARNESS AT STEERING COLUMN) DAYTIME RUNNING LAMPS (DRL) RELAY (ON MAIN SUPPORT BRACKET AT DRIVER'S ISLAND) DAYTIME RUNNING LAMPS (DRL) RELAY 2 DIODE NETWORK DK BLU WIRE DK GRN/WHT WIRE DRL INDICATOR GAUGES FUSE GRN WIRE HEAD- LAMP DIMMER SWITCH HEADLAMPS SWITCH HI BEAM INDICATOR HI LO HOT AT ALL TIMES HOT IN RUN OR START I/P FUSE BLOCK IGNITION SWITCH INSTRUMENT CLUSTER INSTRUMENT CLUSTER SYSTEM LEFT HEAD- LAMP LEFT HI BEAM HEAD- LAMP LO HI LOCK OFF LT GRN WIRE LT GRN/BLK WIRE NEAR BREAKOUT FOR CHASSIS HARNESS) ORG/ WIRE PARK BRAKE IN FOG LAMPS PARK BRAKE INDICATOR SWITCH (ON PARK BRAKE) PARK HEAD OFF PNK IGNITION LAMP FEED HI BM FEED HI BM INDICATOR DRL RELAY CTRL GROUND WIRE PNK WIRE RIGHT HEAD- LAMP RIGHT HI BEAM HEAD- LAMP RUN WIRE TAN WIRE TAN/WHT WIRE WHT WIRE YEL WIRE

1996 VFTC ACCY BLK WIRE BLK/WHT WIRE BULB TEST DAYTIME RUNNING LAMPS (DRL) MODULE (ATTACHED TO I/P HARNESS AT STEERING COLUMN) DAYTIME RUNNING LAMPS (DRL) RELAY (ON MAIN SUPPORT BRACKET AT DRIVER'S ISLAND) DIODE NETWORK DK BLU WIRE DK GRN/WHT WIRE DRL INDICATOR GAUGES FUSE GRN WIRE HEAD- LAMP DIMMER SWITCH HEADLAMPS SWITCH HI LO HOT AT ALL TIMES HOT IN RUN OR START I/P FUSE BLOCK IGNITION SWITCH INSTRUMENT CLUSTER INSTRUMENT CLUSTER SYSTEM HI BEAM INDICATOR LEFT HEAD- LAMP LO HI LOCK OFF LT GRN WIRE LT GRN/BLK WIRE NEAR BREAKOUT FOR CHASSIS HARNESS) ORG/ WIRE PARK BRAKE IN FOG LAMPS PARK BRAKE INDICATOR SWITCH (ON PARK BRAKE) PARK HEAD OFF PNK IGNITION LAMP FEED HI BM FEED HI BM INDICATOR DRL RELAY CTRL GROUND WIRE PNK WIRE RIGHT HEAD- LAMP RUN WIRE TAN WIRE TAN/WHT WIRE WHT WIRE YEL WIRE

4 13 PNK WIRE A/T ABS IND. ACCY BULB TEST LOCK OFF ANTI-LOCK BRAKES SYSTEM AUTO PARK IND. BLK WIRE BLK/WHT WIRE BRAKE IND DRL IND BRN/WHT WIRE CHECK GAUGES IND COOLANT TEMPERATURE GAUGE DIESEL DK BLU WIRE DK GRN WIRE DOOR AJAR IND ECM 1 FUSE 12 ENGINE CONTROLS OR STARTING/ CHARGING SYSTEM ENGINE CONTROLS SYSTEM ENGINE CONTROLS SYSTEM ENGINE CONTROLS SYSTEM ENGINE COOLANT LEVEL SWITCH (ON LOWER LEFT END OF RADIATOR SURGE TANK) FUEL GAUGE FUEL SENDER (ON TOP OF FUEL TANK) GAS GAUGES FUSE 8 GRY WIRE GRY/BLK WIRE HEADLIGHTS SYSTEM HI-BEAM IND HOT IN RUN OR START I/P FUSE BLOCK (BEHIND DASH PANEL) (BODY BUILDER INSTALLED) IGNITION SWITCH ILLUMINATION IN-LINE CONNECTOR PROVISIONS FOR BODY BUILDER INSTRUMENT CLUSTER INTERIOR LIGHTS SYSTEM WARNING SYSTEMS LEFT TURN IND LOW COOLANT IND LT BLU WIRE LT GRN (OR WHT) WIRE LT GRN WIRE LT GRN/BLK WIRE MALFUNCTION IND. LAMP (MIL) (SERVICE ENGINE SOON IND) OIL PRESSURE GAUGE PNK WIRE PPL PPL DIESEL PPL GAS PPL RIGHT TURN IND RUN WIRE SEAT BELT IND SERVICE THROTTLE SOON IND SPEEDOMETER TACHOMETER TAN WIRE TAN/WHT WIRE VEHICLE CONTROL MODULE (ON LEFT SIDE OF RADIATOR SUPPORT) VOLTMETER VSS CALIBRATOR (LEFT SIDE OF DRIVER'S ISLAND, UNDER RELAY BRACKET) WAIT TO START IND WATER IN FUEL IND WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

ACCY AUTO APPLY FUSE 19 BATTERY JUNCTION BLOCK BLK WIRE BLK/WHT WIRE BRAKE PRESSURE DIFFERENTIAL SWITCH (INTERNAL TO ELECTRONIC BRAKE CONROL MODULE) DAYTIME RUNNING LAMPS MODULE DIODE DIODE NETWORK (DASH HARN, DK GRN WIRE ELECTRONIC BRAKE CONTROL MODULE (EBCM) (BELOW RADIATOR, ON LOWER CROSSMEMBER) FROM FUSE BLOCK) FUSE BLOCK FUSIBLE LINK GAS DIESEL HOT AT ALL TIMES HOT IN RUN OR START I/P FUSE BLOCK (BEHIND DASH PANEL) (BODY BUILDER INSTALLED) IGNITION SWITCH LOCK OFF LT BLU WIRE LT GRN WIRE NCA WIRE ORG/ WIRE PARK BRAKE ACTUATOR POSITION SWITCH PARK BRAKE ALARM PARK BRAKE ALARM RELAY (ON I/P HARNESS) (BODY BUILDER INSTALLED) PARK BRAKE PULL BUTTON RELAY (ON I/P HARNESS) (BODY BUILDER INSTALLED) PARK/NEUTRAL POSITION SWITCH RELAY (ON RIGHT SIDE OF DRIVER'S ISLAND) PNK PNK WIRE PNK WIRE PNK/BLK WIRE PPL RED WIRE RUN WIRE SHIFT INTERLOCK SYSTEM TAN/WHT WIRE W/ DRL W/ DRL W/O DRL PARK BRAKE INDICATOR SWITCH (BODY BUILDER INSTALLED) W/O DRL WHT WIRE YEL WIRE YEL/BLK WIRE

15 16 17 PPL PPL 2-3 SHIFT SOL CTRL ANTI-LOCK BRAKE SYSTEM BLK LT BLU/ WIRE BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE CAM POSIT SENS RTN FUEL LEV SIGNAL PPL CAM POSIT SENS SIG POWER PNK WIRE CAMSHAFT POSITION (CMP) SENSOR (IN DISTRIBUTOR) DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE GRY WIRE HALL EFFECT SENSOR HALL EFFECT SENSOR PNK WIRE IDLE AIR CONTROL (IAC) VALVE KNOCK SENS SIG KNOCK SENSOR (KS) (LOWER RIGHT SIDE OF ENGINE) LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/ BLK WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE MAP SENSOR IN IAT SENS SIG ECT SENSOR IN THROTTLE POSIT SENS TANK PRESSURE NCA WIRE PNK PNK 30 31 WIRE PNK PNK PNK 1 2 3 WIRE PNK WIRE PNK/BLK WIRE PPL PPL CKP SENS RTN VSS RTN VSS SIG PPL PPL PPL/ WHT WIRE PPL/WHT WIRE PURGE VENT RED/BLK WIRE TAN WIRE TAN/WHT WIRE TANK PRESSURE SENSOR (TOP OF FUEL TANK) VEHICLE CONTROL MODULE (VCM) (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED OUT VEHICLE SPEED SENSOR (VSS) (LEFT REAR OF TRANSMISSION, NEAR CENTER) WHT DK GRN/ WIRE WHT LT BLU/ WIRE WHT LT GRN/ WIRE WHT TAN/ WIRE WHT WIRE YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOLENOID 15 16 17 PPL PPL 2-3 SHIFT SOLENOID AUTOMATIC TRANSMISSION (A/T) (IF EQUIPPED) (REAR OF ENGINE) BLK WIRE BLK/WHT WIRE BRN WIRE DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE ECM 1 FUSE 12 ENG 1 FUSE 15 FUEL INJECTOR 1 FUEL INJECTOR 2 FUEL INJECTOR 3 FUEL INJECTOR 4 FUEL INJECTOR 5 FUEL INJECTOR 6 FUEL INJECTOR 7 FUEL INJECTOR 8 GRY WIRE HOT IN RUN, START I/P FUSE BLOCK (DASH PANEL PROVIDED BY BODY BUILDER) (BODY BUILDER INSTALLED) LT BLU WIRE LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE PNK 5 6 WIRE PNK PNK 30 31 WIRE PNK PNK PNK 1 2 3 WIRE PNK PNK PNK PNK 1 2 3 4 WIRE PNK PNK PNK WIRE PNK PNK WIRE PNK WIRE PNK/BLK WIRE PPL PPL 8 9 10 11 12 13 14 15 16 17 PPL/ WHT WIRE PPL/WHT WIRE PRESSURE CONTROL SOLENOID (PCS) RED WIRE RED/BLK WIRE REV TAN WIRE TAN/ WHT WIRE TAN/WHT WIRE TCC PWM SOLENOID TRANSMISSION FLUID TEMPERATURE SENSOR TRANSMISSION RANGE (TR) PRESSURE SWITCH ASSEMBLY WHT WIRE YEL WIRE YEL/BLK WIRE

2 3 PPL 2-3 SHIFT SOL CTRL ANTI-LOCK BRAKES SYSTEM BANK 2 SENSOR 1 (ON RIGHT EXHAUST PIPE BEFORE CATALYTIC CONVERTER) BLK LT BLU/ WIRE BLK WIRE BLK/WHT WIRE BLU/BLK WIRE BRN WIRE BRN/WHT WIRE CAMSHAFT POSITION SENSOR (INTERNAL TO DISTRIBUTOR) CMP LOW FUEL GAUGE PPL DK BLU WIRE DK BLU/WHT WIRE GRN/BLK WIRE HEATED OXYGEN IGN FEED KS SIGNAL LEFT KNOCK SENSOR (ON LOWER LEFT SIDE OF ENGINE) LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/ BLK WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE MAP SIGNAL IAT SIGNAL ECT SIGNAL NCA WIRE PNK 8 9 10 WIRE PNK IGN FEED SENS RTN SENS SIG WIRE PNK WIRE PNK/BLK WIRE PPL PPL CKP LOW VSS LOW VSS SIGNAL PPL PPL PPL/WHT WIRE RED/BLK WIRE RIGHT KNOCK SENSOR (ON LOWER RIGHT SIDE OF ENGINE) SENSOR RTN SENSOR SIGNAL T/P SIGNAL TAN WIRE TAN/WHT WIRE TFT SIGNAL MAF SIGNAL IAC HIGH IAC LOW INJECTOR 4 CTRL INJECTOR 3 CTRL VEHICLE CONTROL MODULE (VCM) (CENTER FRONT OF ENGINE COMPARTMENT) VSS WHT LT BLU/ WIRE WHT LT GRN/ WIRE WHT PPL/ WIRE YEL WIRE YEL/BLK WIRE

2 3 PPL AUTOMATIC TRANSMISSION BANK 1 SENSOR 1 (ON LEFT EXHAUST PIPE BEFORE CATALYTIC CONVERTER) BANK 1 SENSOR 2 (ON LEFT EXHAUST PIPE AFTER CATALYTIC CONVERTER) BANK 2 SENSOR 2 (ON RIGHT EXHAUST PIPE AFTER CATALYTIC CONVERTER) BLK WIRE BLK/WHT WIRE BLU WIRE BLU/BLK WIRE BRN WIRE DK BLU WIRE DK BLU/WHT WIRE ECM 1 FUSE 12 ENG 1 FUSE 15 EXHAUST GAS RECIRCULATION VALVE SOLENOID (LEFT SIDE OF INTAKE PLENUM) FLUID TEMPERATURE SENSOR (INTERNAL) FORCE MOTOR FUEL INJ 1 FUEL INJ 2 FUEL INJ 3 FUEL INJ 5 FUEL INJ 4 FUEL INJ 6 FUEL INJ 7 FUEL INJ 8 GRN WIRE GRN/BLK WIRE GRY WIRE HEATED OXYGEN HOT IN RUN AND START I/P FUSE BLOCK IGNITION INTAKE AIR TEMP SENSOR (MOUNTED IN FRESH AIR INTAKE BEHIND AIR FILTER BOX) LT BLU/WHT WIRE LT GRN WIRE NCA WIRE PNK 8 9 10 WIRE PNK PNK 2 3 WIRE PNK PNK WIRE PNK WIRE PNK/BLK WIRE PPL PPL PNK 9 10 11 12 13 14 15 WIRE PPL/ WHT WIRE PPL/WHT WIRE RED WIRE RED/BLK WIRE SOLENOID 1-2 SOLENOID 2-3 SWITCH PRESSURE TAN WIRE TAN/ WHT WIRE TAN/WHT WIRE TCC SOLENOID WHT LT BLU/ WIRE WHT PPL/ WIRE WHT TAN/ WIRE WHT WIRE YEL WIRE YEL/BLK WIRE