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

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

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

1996 VFTC A/C COMPRESSOR CLUTCH RELAY AUXILIARY ENGINE COOLANT FAN RELAY (DIESEL ONLY) BATT BUS BATTERY BATTERY JUNCTION BLOCK (LEFT SIDE OF ENGINE BULKHEAD, ABOVE RELAY BRACKET) BLK WIRE DATA LINK CONNECTOR (DLC) DIESEL DOME LAMP (PROVISIONS FOR) ECM BAT FUSE ENG-BAT FUSE FUEL PUMP RELAY FUEL PUMP SWITCH, ENGINE OIL PRESSURE GAUGE SENSOR FUSIBLE LINK (10 GA-RUST) FUSIBLE LINK (16 GA- FUSIBLE LINK 12 GA. BLUE FUSIBLE LINK 18 GA. BLUE FUSIBLE LINK 18 GA. RUST GAS GENERATOR (RIGHT FRONT OF ENGINE) GLOW PLUG CONTROL SWITCH (DIESEL ONLY) GRY WIRE HAZARD WARNING LAMPS FLASHER HEADLAMPS SWITCH HORN RELAY HORN/ DM FUSE TAIL LPS FUSE I/P FUSE BLOCK (DASH PANEL PROVIDED BY BODY BUILDER) (BODY BUILDER INSTALLED) IGNITION SWITCH ORG/ WIRE PWR BUS PWR FUSE RED WIRE REMOTE BATTERY ACCESS TERMINAL BLOCK (REAR OF RIGHT RADIATOR CORE SUPPORT PANEL) SEAT BELT ALARM SECONDARY BATTERY (DIESEL ONLY) STARTER RELAY STARTER SOLENOID (AT STARTER, LOWER RIGHT SIDE OF ENGINE) STOP/ HAZ FUSE STUD TO HEADLAMPS SWITCH (CAVITY E) TORQUE CONVERTER CLUTCH, STOPLAMPS SWITCH TRANSMISSION CONTROL MODULE (A/T ONLY) VEHICLE CONTROL MODULE (VCM) W/DELUXE SCHOOL BUS

1996 VFTC ACC BUS AUTOMATIC TRANSMISSION AUTOMATIC TRANSMISSION (A/T) BRN WIRE CLUTCH PEDAL POSITION (CPP) SWITCH CRK (START) LOCK ON (RUN) OFF CRK (START) ON (RUN) LOCK OFF CRK (START) ON (RUN) OFF DIESEL DK BLU WIRE ENG 1 FUSE EVAPORATIVE EMISSIONS (EVAP) CANISTER PURGE SOLENOID VALVE FROM FUSIBLE LINK FUEL HEATER FUSE OUTPUT- ACCESSORY TYPE 3 FUSE GAS GLOW PLUG CONTROL SWITCH HEATED OXYGEN SENSOR HEATED OXYGEN SENSOR CAMSHAFT POSITION (CMP) SENSOR I/P FUSE BLOCK (DASH PANEL PROVIDED BY BODY BUILDER) (BODY BUILDER INSTALLED) IGNITION SWITCH LEFT POST CONVERTER (5.7L VIN R LEFT PRE- CONVERTER LINEAR EXHAUST GAS RECIRC- ULATION (EGR) SOLENOID VALVE LOCK MANUAL TRANSMISSION MASS AIR FLOW (MAF SENSOR) NCA WIRE ORG/ WIRE PARK/NEUTRAL POSITION (PNP), BACKUP LAMPS SWITCH PNK PNK WIRE PNK WIRE POST CONVERTER (4.3L VIN W PROVISIONS FOR WIPER/ WASHER MOTOR RADIO FUSE RED WIRE RIGHT POST CONVERTER (5.7L VIN R RIGHT PRE- CONVERTER TO I/P FUSE BLOCK: (AUX, I-3, TURN B/U,, HTR FUSES) TRANS FUSE VEHICLE CONTROL MODULE (VCM) WATER- IN-FUEL SENSOR AUXILIARY ENGINE COOLANT FAN RELAY WHT WIRE WINDSHIELD WIPER/ WASHER SWITCH WIPER FUSE YEL WIRE

1996 VFTC 6.5L VIN Y A/C COMPRESSOR CLUTCH RELAY AUTOMATIC TRANSMISSION AUX FUSE BACK UP LAMPS SWITCH BRN WIRE CANADIAN MODELS ONLY CAVITY A) DAYTIME RUNNING LAMP (DRL) RELAY DAYTIME RUNNING LAMPS (DRL) CONTROL MODULE DIESEL ECM 1 FUSE FROM IGNITION SWITCH FUEL INJECTION PUMP FUEL SHUT-OFF SOLENOID GAS GAS MODELS ONLY GAUGES FUSE GENERATOR GENERATOR HOT IN RUN, START HTR BUS HTR FUSE I-3 FUSE I/P FUSE BLOCK (DASH PANEL PROVIDED BY BODY BUILDER) (BODY BUILDER INSTALLED) IGN BUS INSTRUMENT CLUSTER MANUAL TRANSMISSION ORG/ WIRE P/B BOOSTER FLUID FLOW, PRESSURE ALARM PARK/ NEUTRAL POSITION (PNP), BACKUP LAMPS SWITCH PNK PNK WIRE PNK WIRE SEAT BELT ALARM INSTRUMENT CLUSTER THIS CAN PLUG INTO TORQUE CONVERTER CLUTCH (TCC), STOP LAMPS SWITCH TRANSMISSION CONTROL MODULE (TCM) FUEL INJECTION PUMP FUEL SHUT-OFF SOLENOID TURN SIGNAL FLASHER TURN-B/U FUSE VEHICLE CONTROL MODULE (VCM) VEHICLE SPEED SENSOR (VSS) BUFFER W/BRAKE WARNING INDICATOR SYSTEM

1996 VFTC 7.20 +/- 1.20 OHMS BRN WIRE DASH LAMPS INPUT DK GRN WIRE FROM I/P FUSE BLOCK (TAIL LAMPS FUSE) GRY WIRE HEAD OFF PARK HEADLAMPS SWITCH I/P LAMPS DIMMER SWITCH INSTRUMENT CLUSTER LICENSE LAMPS, LEFT REAR LICENSE LAMPS, RIGHT REAR MARKER LAMPS (PROVISIONS FOR) ORG/ WIRE PANEL ILLUMINATION PANEL LAMPS SWITCH PARK PARK, TURN SIGNAL (T/S) LAMP LEFT FRONT PARK, TURN SIGNAL (T/S) LAMP RIGHT FRONT PRNDL LAMP SEAT BELT ALARM SIDE MARKER LAMP LEFT FRONT SIDE MARKER LAMP RIGHT FRONT SIDE MARKER LAMP, LEFT REAR (PROVISIONS FOR) SIDE MARKER LAMP, RIGHT REAR (PROVISIONS FOR) TAIL TAIL, STOP/TURN SIGNAL LAMPS LEFT (PROVISIONS FOR) TAIL, STOP/TURN SIGNAL LAMPS RIGHT (PROVISIONS FOR)

1996 VFTC 6.5L VIN F 6.5L VIN F 7.4L VIN J 7.4L VIN J (L29), 6.5L VIN F (L65) ENGINES ONLY 7.4L VIN N A/C COMPRESSOR CONTROL RELAY BATTERY BATTERY JUNCTION BLOCK (ON FORWARD LEFT SIDE OF THE BULKHEAD) BLANK FUSE BLK WIRE BUSS BAR DATA LINK CONNECTOR (DLC) DIESEL ONLY DOME LAMP ENG-BAT FUSE FAN CONTROL RELAY FUEL PUMP RELAY FUSIBLE LINK (10 GA-RUST) FUSIBLE LINK (14 GA- FUSIBLE LINK (16 GA- FUSIBLE LINK 12 GA. BLUE FUSIBLE LINK 18 GA. BLUE GENERATOR (ON RIGHT FRONT OF ENGINE) GLOW PLUG CONTROL RELAY HAZARD LAMPS FLASHER HEADLAMPS SWITCH HORN RELAY HORN- DM FUSE I/P FUSE BLOCK (MOUNTED ON THE I/P) IGNITION SWITCH ONLY ORG/ WIRE POWERTRAIN CONTROL MODULE (PCM) POWERTRAIN CONTROL MODULE (PCM) VEHICLE CONTROL MODULE (VCM) PWR CIRCUIT BREAKER RED WIRE SEAT BELTS/ LAMPS ALARM MODULE SECONDARY BATTERY (DIESEL ONLY) STARTER MOTOR (ON RIGHT REAR SIDE OF ENGINE) STARTER RELAY STOP- HAZ FUSE ECM- BAT FUSE TAIL LAMPS FUSE TO HEADLAMPS SWITCH (CAVITY E) TORQUE CONVERTER CLUTCH (TCC), STOPLAMPS SWITCH

14 GA (BLK) WIRE 1996 VFTC 7.4L VIN J (L29) ENGINE, 7.4L VIN N (L19) ENGINE 7.4L VIN J, 6.5L VIN F ENGINES AUTOMATIC TRANSMISSION BRN WIRE CAMSHAFT POSITION SENSOR (7.4L VIN J DK BLU WIRE ECM-1 FUSE,, GAUGES FUSE ENG-1 FUSE TRANS FUSE ENGINE EVAPORATIVE EMISSIONS CANISTER PURGE SOLENOID (7.4L VIN J FAN CONTROL RELAY FROM FUSIBLE LINK FUEL HEATER (6.5L VIN F ENGINE) FUSE OUTPUT- ACCESSORY TYPE 3 FUSE GLOW PLUG CONTROL RELAY (6.5L VIN F ENGINE) HEATED OXYGEN SENSOR NO.1 HEATED OXYGEN SENSOR NO.2 HEATED OXYGEN SENSOR NO.3 HEATED OXYGEN SENSOR NO.4 I/P AUXILIARY FUSE BLOCK (MOUNTED ON I/P FUSE BLOCK) CRANK FUSE I/P FUSE BLOCK (MOUNTED ON THE I/P) IGNITION COIL (7.4L VIN N ENGINE) IGNITION SWITCH LOCK OFF MASS AIR FLOW SENSOR (7.4L VIN J ENGINE) NCA WIRE ORG/ WIRE PNK PNK WIRE PNK WIRE PPL PROVISIONS FOR WIPER/WASHER MOTOR RADIO FUSE RED WIRE RUN WIRE STARTER SOLENOID (7.4L VIN N ENGINE) VEHICLE CONTROL MODULE LINEAR EGR SOLENOID VALVE WATER IN-FUEL INDICATOR SENSOR (6.5L VIN F ENGINE) WHT WIRE WIPER FUSE YEL WIRE

1996 VFTC 6.5L VIN F PNK ONLY WIRE 7.4L VIN J (L29), 6.5L VIN F (L65) ENGINES 7.4L VIN J, 6.5L VIN F (L65) ENGINES ONLY PNK WIRE 7.4L VIN N A/C COMPRESSOR CONTROL RELAY AUTO APPLY PARK BRAKE SWITCH AUX CIRCUIT BREAKER BACKUP LAMP SWITCH BRN WIRE BUSS BAR CANADIAN MODELS CAVITY A) CRUISE CONTROL MODULE DAYTIME RUNNING LAMPS MODULE DAYTIME RUNNING LAMPS RELAY ENGINE FROM IGNITION SWITCH GAUGES FUSE GENERATOR HOT IN RUN, START HTR FUSE I-3 FUSE I/P AUXILIARY FUSE BLOCK (MOUNTED ON THE I/P FUSE BLOCK) AUTO APPLY FUSE I/P FUSE BLOCK (MOUNTED ON THE I/P) INSTRUMENT CLUSTER NCA WIRE ORG/ WIRE PARK BRAKE LOW PRESSURE SWITCH PARK/NEUTRAL POSITION (PNP), BACKUP LAMP SWITCH PNK PNK WIRE PNK WIRE PPL SEATBELTS/ LAMPS ALARM MODULE SPEED CONTROL SWITCH TORQUE CONVERTER CLUTCH, STOPLAMPS SWITCH TURBO CHARGER POWER VALVE SOLENOID TURN SIGNAL FLASHER TURN SIGNAL SWITCH TURN-B/U FUSE VEHICLE CONTROL MODULE (VCM)

1996 VFTC BRN WIRE DK GRN WIRE FROM I/P FUSE BLOCK (TAIL LAMPS FUSE) FULL DIM GRY WIRE HEAD OFF PARK HEADLAMPS SWITCH I/P FUSE BLOCK (MOUNTED ON I/P) I/P FUSE BLOCK (MOUNTED ON THE I/P) INSTR- LPS FUSE INSTRUMENT CLUSTER INSTRUMENT PANEL DIMMER SWITCH LAMP ON INPUT LICENSE LAMP, LEFT REAR (PROVISIONS FOR) LICENSE LAMP, RIGHT REAR (PROVISIONS FOR) LIGHT SWITCH ORG/ WIRE PANEL ILLUMINATION PANEL LAMPS PARK PARK, TURN SIGNAL (T/S) LAMP LEFT FRONT PARK, TURN SIGNAL (T/S) LAMP RIGHT FRONT ROOF MARKER LAMPS (PROVISIONS FOR) SEATBELTS/ LAMPS ALARM MODULE SIDE MARKER LAMP LEFT FRONT (PROVISIONS FOR) SIDE MARKER LAMP RIGHT FRONT (PROVISIONS FOR) SIDE MARKER LAMP, LEFT REAR (PROVISIONS FOR) SIDE MARKER LAMP, RIGHT REAR (PROVISIONS FOR) TAIL, STOP, TURN SIGNAL (T/S) LAMPS, LEFT (PROVISIONS FOR) TAIL, STOP, TURN SIGNAL (T/S) LAMPS, RIGHT (PROVISIONS FOR) TRANSMISSION RANGE INDICATOR LAMP