GMC Forward Control P3500 (1985-1999) ecm 1 fuse 12 Wiring diagrams

1-2 SHIFT SOL 1-2 SHIFT SOLENOID 2-3 SHIFT SOL 2-3 SHIFT SOLENOID A/C COMPRESSOR RELAY, GENERATOR, SEAT BELT/ HEADLAMPS ALARM MODULE A/T INPUT SPEED SENSOR (LEFT SIDE OF TRANSMISSION) A/T ISS HI IN A/T ISS LO IN A/T OUTPUT SPEED SENSOR ANTI-LOCK BRAKES, CRUISE CONTROL, SHIFT INTERLOCK SYSTEMS AUTOMATIC TRANSMISSION BATTERY IN BLK WIRE BLK/WHT WIRE BRAKE SWITCH INPUT BRN WIRE BRN/WHT WIRE BUSS BAR GAUGES FUSE 8 DATA CLASS II DK BLU WIRE DK BLU/WHT WIRE ECM 1 FUSE 12 ECM-BAT FUSE 6 ECT SENS INPUT ELECTRONIC BRAKE CONTROL MODULE, CRUISE CONTROL MODULE ENGINE CONTROLS SYSTEM FUEL INJECTORS (ENGINE CONTROLS SYSTEM) FUEL PUMP RELAY, SWITCH GRY WIRE HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START I-3 FUSE 9 I/P FUSE BLOCK IGNITION IN INSTRUMENT CLUSTER LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MIL CONTROL ORG/ WIRE PCM GROUND PCS SOL HI OUT PCS SOL LO OUT PNK WIRE PPL PPL DATA LINK CONNECTOR (PARTIAL) (BELOW DASH NEAR STEERING COLUMN) PPL/WHT WIRE PRESS CTRL SOLENOID RANGE SIGNAL "A" RANGE SIGNAL "B" RANGE SIGNAL "C" RED WIRE RED/BLK WIRE SENSOR GROUND SENSOR RETURN SERVICE ENGINE SOON INDICATOR TCC PWM SOL TCC PWM SOLENOID TCC/ STOP LAMPS SWITCH TP SENS INPUT TRANS FLUID TEMP SENSOR TRANS FUSE 17 TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANS TEMP SIG IN TWISTED WIRE PAIR VEHICLE CONTROL MODULE (CENTER FRONT OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT REAR OF TRANSMISSION) VSS HI VSS LO YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOL 1-2 SHIFT SOLENOID 2-3 SHIFT SOL 2-3 SHIFT SOLENOID 3-2 SHIFT SOL 3-2 SHIFT SOLENOID A/C COMPRESSOR RELAY, GENERATOR, TURBO CHARGER POWER VALVE A/T INPUT SPEED SENSOR (LEFT SIDE OF TRANSMISSION) A/T ISS SENS HI IN A/T ISS SENS LO IN ACCELERATOR PEDAL POSITION MODULE (ATTACHED TO ACCELERATOR PEDAL) APP 1 SIGNAL IN APP 2 SIGNAL IN APP 3 SIGNAL IN AUTOMATIC TRANSMISSION BATTERY IN BLK WIRE BLK/WHT WIRE BRAKE SWITCH IN BRN WIRE BRN/WHT WIRE BUSS BAR CLASS II DATA DATA LINK CONNECTOR (PARTIAL) (BELOW DASH, NEAR STEERING COLUMN) DK BLU WIRE DK BLU/WHT WIRE DK GRN/WHT WIRE ECM 1 FUSE 12 ECM-BAT FUSE 6 ECT SENSOR IN ELECTRONIC BRAKE CONTROL MODULE ENGINE COOLANT TEMPERATURE SENSOR (TOP FRONT OF ENGINE) FUEL PUMP RELAY, FUEL PUMP SWITCH/ENGINE OIL PRESSURE INDICATOR SENSOR GAUGES FUSE 8 GRY WIRE HAZARD LAMPS FLASHER (ABOVE STEERING COLUMN) HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START I-3 FUSE 9 I/P FUSE BLOCK IGNITION IN INSTRUMENT CLUSTER LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MIL CONTROL ORG/ WIRE PCM GROUND PCS SOL HI OUT PCS SOL LO OUT PNK INSTRUMENT CLUSTER WIRE PNK WIRE POWERTRAIN CONTROL MODULE (LEFT SIDE OF DRIVER'S ISLAND) PPL PPL/WHT WIRE PRESS CTRL SOLENOID RED WIRE RED/BLK WIRE SENSOR GROUND SERVICE ENGINE SOON INDICATOR STOP-HAZ FUSE 11 STOPLAMP SWITCH IN TFT SENSOR IN TORQUE CONVERTER CLUTCH BRAKE, STOPLAMP SWITCH TRANS FLUID TEMP SENSOR TRANS RANGE "A" TRANS RANGE "B" TRANS RANGE "C" TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANSMISSION FUSE 17 TWISTED WIRE PAIR VEHICLE SPEED SENSOR (LEFT REAR OF TRANSMISSION) VEHICLE SPEED SENSOR CALIBRATOR (ABOVE ACCELERATOR PEDAL) VEHICLE SPEED SENSOR CALIBRATOR, ENGINE SHUTOFF SOLENOID VSS HI IN VSS LO IN VSS OUT YEL WIRE YEL/BLK WIRE

ABS IND. ACCY ACCY ANTI-LOCK BRAKES SYSTEM BLK WIRE BLK/WHT WIRE BRAKE IND BRAKE PRESSURE DIFFERENTIAL SWITCH (INTERNAL TO ELECTRONIC BRAKE CONROL MODULE) BRN/WHT WIRE CHECK GAUGES IND COOLANT TEMPERATURE GAUGE DIESEL DIODE NETWORK (DASH HARN, DK BLU WIRE DK GRN WIRE DOOR AJAR IND DRL IND ECM 1 FUSE 12 ELECTRONIC BRAKE CONTROL MODULE (EBCM) (BELOW RADIATOR, ON LOWER CROSSMEMBER) ENG 1 FUSE 15 ENGINE CONTROLS OR STARTING/CHARGING SYSTEM ENGINE CONTROLS SYSTEM ENGINE CONTROLS SYSTEM ENGINE CONTROLS SYSTEM TRANSMISSIONS SYSTEM ENGINE COOLANT LEVEL SWITCH (ON LOWER LEFT END OF RADIATOR SURGE TANK) FOOT BRAKE (PARK BRAKE APPLY OPPTION) FUEL GAUGE FUEL SENDER (ON TOP OF FUEL TANK) GAS GAUGES FUSE 8 GRY WIRE GRY/BLK WIRE HAND BRAKE HEADLIGHTS SYSTEM HI-BEAM IND HOT IN RUN OR START I/P FUSE BLOCK I/P FUSE BLOCK (BODY BUILDER INSTALLED) I/P FUSE BLOCK) INSTRUMENT CLUSTER IGNITION SWITCH ILLUMINATION IN-LINE CONNECTOR PROVISIONS FOR BODY BUILDER INTERIOR LIGHTS SYSTEM WARNING SYSTEMS LEFT TURN IND LOCK LOCK OFF OFF LOW COOLANT IND LT BLU WIRE LT BLU/BLK WIRE LT GRN (OR WHT) WIRE LT GRN WIRE MALFUNCTION IND (MIL) (SERVICE ENGINE SOON IND) NCA WIRE OIL PRESSURE GAUGE PNK 4 13 WIRE 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 TRANS IND. VEHICLE CONTROL MODULE (ON LEFT SIDE OF RADIATOR SUPPORT) VOLTMETER VSS CALIBRATOR (LEFT SIDE OF DRIVER'S ISLAND, UNDER RELAY BRACKET) W/ DRL W/O DRL WAIT TO START IND WATER IN FUEL IND WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK 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

5.7L VIN R CRANKSHAFT POSITION SENSOR ECM 1 FUSE 12 FROM BREAKOUT TO RIGHT OXYGEN SENSOR) FROM ENG-1 FUSE (DIAGRAM 2 OF 4) FUEL INJECTOR 1 FUEL INJECTOR 2 FUEL INJECTOR 3 FUEL INJECTOR 4 FUEL INJECTOR 5 FUEL INJECTOR 6 FUEL INJECTOR 7 FUEL INJECTOR 8 I/P FUSE BLOCK (DASH PANEL PROVIDED BY BODY BUILDER) IGNITION COIL IGNITION COIL VEHICLE CONTROL MODULE IGNITION CONTROL MODULE INSTRUMENT CLUSTER INSTRUMENT CLUSTER IGNITION CONTROL MODULE PNK PNK WIRE PNK WIRE VEHICLE CONTROL MODULE

1996 VFTC 6.5L ENGINE A/C COMPRESSOR RELAY A/T AUX CIRCUIT BREAKER 13 AUX FUSE BACK UP LAMPS SWITCH BRN WIRE CB CB I-3 FUSE 9 DAYTIME RUNNING LAMP RELAY INSTRUMENT CLUSTER DAYTIME RUNNING LAMPS CONTROL MODULE DIESEL DK GRN WIRE ECM 1 FUSE 12 ELECTRONIC BRAKE CONTROL MODULE FROM ENG-1 FUSE (DIAGRAM 2 OF 4) FROM IGNITION SWITCH (DIAGRAM 2 OF 4) FROM VCM BREAKOUT) FUEL INJECTION PUMP SHUT-OFF SOLENOID GAS GAUGES FUSE 8 GENERATOR GENERATOR GLOW PLUG CONTROLLER (FEDERAL) GRY WIRE HTR BUS HTR FUSE 1 I/P FUSE BLOCK (DASH PANEL PROVIDED BY BODY BUILDER) IGN BUS INSTRUMENT CLUSTER INSTRUMENT LAMPS FUSE INTERIOR LIGHTS SYSTEM (I/P LAMPS DIMMER SWITCH) M/T ORG/ WIRE OTHERS PARK/ NEUTRAL POSITION AND BACKUP LAMPS SWITCH PNK (ENGINE HARNESS, APPROX 26 CM FROM BULKHEAD GROMMET) WIRE PNK PNK PNK WIRE PNK PNK WIRE PNK WIRE POWERTRAIN CONTROL MODULE (ELEC) SEAT BELTS ALARM MODULE TORQUE CONVERTER CLUTCH, STOP LAMPS SWITCH TURN B/U FUSE 5 TURN SIGNAL FLASHER VEHICLE CONTROL MODULE (VCM) WATER IN FUEL INDICATOR SENSOR FUEL HEATER GLOW PLUG CONTROLLER (CALIF)

6.5L VIN F CRANKSHAFT POSITION SENSOR ECM 1 FUSE 12 FEDERAL FROM GAUGES FUSE DIAGRAM 4 OF 4) FUEL HEATER GLOWPLUG CONTROLLER I/P FUSE BLOCK (MOUNTED ON THE DASH) IGNITION COIL IGNITION CONTROL MODULE INJECTOR 1 INJECTOR 2 INJECTOR 3 INJECTOR 4 INJECTOR 5 INJECTOR 6) INJECTOR 7 (-) INJECTOR 8 (-) INSTRUMENT CLUSTER PNK PNK WIRE PNK WIRE POWERTRAIN CONTROL MODULE VEHICLE CONTROL MODULE VEHICLE SPEED SENSOR CALIBRATOR WASTEGATE SOLENOID GLOWPLUG CONTROLLER WATER IN FUEL INDICATOR SENSOR

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

5 VOLT REF ACCELERATOR PEDAL POSITION MODULE (ATTACHED TO ACCELERATOR PEDAL) APP 1 SENSOR APP 2 SENSOR APP 3 SENSOR BLK WIRE BRN WIRE BRN/WHT WIRE CLOSURE GRD CLOSURE SIGNAL DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE ECM 1 FUSE 12 ENGINE SHUTOFF SOLENOID FUEL SOL CTRL FUEL SOL HIGH FUEL SOL LOW FUEL SOLE- NOID FUEL SOLENOID DRIVER (TOP LEFT OF ENGINE) GRN WIRE GRY WIRE HAZARD FLASHER (INNER LEFT SIDE OF MAIN SUPPORT BRACKET) HIGH LOW HIGH RES SIG HOT AT ALL TIMES HOT IN HOT IN RUN AND START I-3 FUSE 9 I/P FUSE BLOCK IGNITION IGNITION TIMING STEPPER MOTOR (PART OF FUEL INJECTION PUMP) LOW HIGH LT BLU WIRE LT GRN WIRE OPTICAL FUEL TEMPERATURE SENSOR (PART OF FUEL INJECTION PUMP) ORG/ WIRE ORG/BLK WIRE PNK PNK PPL 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 WIRE PNK WIRE PNK/BLK WIRE PPL PPL PPL PPL PPL 28 29 30 31 32 PUMP CAM SIG RED WIRE RED/BLK WIRE RUN WIRE SENSOR GROUND STOP-HAZ FUSE 11 TAN WIRE TAN/BLK WIRE TCC/ STOPLAMP SWITCH (AT REAR OF BRAKE PEDAL SUPPORT BRACKET) TRANS FUSE 17 WHT 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