GMC Forward Control P3500 (1985-1999) blk Wiring diagrams

1-3 FUSE 9 A/T ISS HIGH A/T ISS LOW AUTOMATIC TRANSMISSION SHAFT SPEED SENSOR (A/T ISS) (LEFT SIDE OF TRANSMISSION) BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRN WIRE CRUISE CONTROL MODULE (ON LEFT RADIATOR SUPPORT BRACKET) CRUISE CONTROL SWITCH CRUISE ENGAGED IN VSS INPUT DK BLU WIRE DK GRN/WHT WIRE GRY WIRE GRY/BLK WIRE HAZARD LAMPS FLASHER (LEFT OF STEERING COLUMN) HOT AT ALL TIMES HOT IN RUN I/P FUSE BLOCK LT BLU WIRE LT BLU/BLK WIRE NCA WIRE OFF ORG/ WIRE PPL R/A RED/BLK WIRE RESISTOR (ENGINE HARNESS, 7 CM FROM BREAKOUT TO ENGINE COOLANT FAN MOTOR CONN) S/C STOP/HAZ FUSE 1 STOPLAMPS SWITCH (ABOVE BRAKE PEDAL) TORQUE CONVERTER CLUTCH, STOPLAMPS SWITCH (ABOVE BRAKE PEDAL) VEHICLE CONTROL MODULE (VCM) (ON LEFT RADIATOR SUPPORT BRACKET) VSS OUTPUT CRUISE ENGAGED

2-3 SHIFT SOL CTRL ANTI-LOCK BRAKE SYSTEM BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE CAM POSIT SENS RTN FUEL LEV PPL CAMSHAFT POSITION (CMP) SENSOR (INTERNAL TO DISTRIBUTOR) CKP DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE GRY WIRE HALL EFFECT SENSOR IGN FEED KNOCK SENS SIG KNOCK SENSOR (KS) (TOP CENTER REAR OF ENGINE) LT BLU WIRE LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE NCA WIRE PNK PNK PNK 2 3 4 WIRE PNK WIRE PNK/BLK WIRE PPL PPL CKP SENS RTN VSS RTN VSS SIG PPL/WHT WIRE PURGE VENT CTRL RETURN SENSOR CKP SENSOR SIGNAL TAN WIRE TAN/WHT WIRE TANK PRESSURE SENSOR (TOP OF FUEL TANK) VEHICLE SPEED OUT VEHICLE SPEED SENSOR (VSS) (LEFT SIDE OF TRANSMISSION) WHL SPD SIG, LEFT FRT CAM POSIT SENS SIG WHT DK GRN/ WIRE WHT LT BLU/ WIRE WHT LT GRN/ WIRE WHT WIRE YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOLENOID 2-3 SHIFT SOLENOID AUTOMATIC TRANSMISSION (A/T) (IF EQUIPPED) (REAR OF ENGINE) BLK WIRE BLK/WHT WIRE BRN WIRE DK BLU WIRE DK GRN/WHT WIRE ECM 1 FUSE 12 ENG 1 FUSE 15 FUEL INJECTOR NO.2 FUEL INJECTOR NO.1 FUEL INJECTOR NO.3 FUEL INJECTOR NO.4 FUEL INJECTOR NO.5 FUEL INJECTOR NO.6 GRY WIRE HOT IN RUN, START I/P FUSE BLOCK (BEHIND DASH PANEL) (BODY BUILDER INSTALLED) LT BLU WIRE LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE PNK PNK PNK 2 3 4 5 WIRE PNK PNK PNK 2 3 4 WIRE PNK PNK WIRE PNK WIRE PNK/BLK WIRE PPL PPL/WHT WIRE PRESSURE CONTROL SOLENOID (PCS) RED WIRE RED/BLK WIRE REV TAN WIRE TAN/WHT WIRE TCC PWM SOLENOID TRANS FUSE 17 TRANSMISSION FLUID TEMPERATURE (TFT) SENSOR TRANSMISSION RANGE (TR) PRESSURE SWITCH ASSEMBLY WHT WIRE YEL WIRE YEL/BLK WIRE

3 4 5 PNK PNK WIRE A/C COMPRESSOR HIGH PRESSURE CUT-OFF SWITCH (REAR OF A/C COMPRESSOR) BLK WIRE BREAKOUT) BRN WIRE BRN/WHT WIRE DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ENG BAT FUSE 10 ENGINE COOLANT TEMPERATURE (ECT) SENSOR (TOP FRONT OF ENGINE) FROM ECT SENSOR BREAKOUT) FUEL GAUGE FUEL SENDER, FUEL PUMP (TOP OF FUEL TANK) GAUGES FUSE 8 GRY WIRE HOT AT ALL TIMES HOT IN RUN, START I/P FUSE BLOCK (BEHIND DASH PANEL) (BODY BUILDER INSTALLED) INSTRUMENT CLUSTER LT BLU/WHT WIRE LT GRN WIRE MALFUNCTION INDICATOR LAMP MAP REF LO MASS AIR FLOW SENSOR (MAF) (MOUNTED IN FRESH AIR INTAKE, BEHIND AIR FILTER BOX) NCA WIRE ORG/ WIRE PNK 6 7 8 9 10 11 12 13 14 15 WIRE PNK PNK PNK 2 3 4 5 WIRE PNK PNK WIRE PNK WIRE PPL RED WIRE RED/BLK WIRE REF LO REF THROTTLE POSITION (TP) SENSOR (ON THROTTLE BODY, TOP OF ENGINE) SENSOR BREAKOUT) SPEEDO- METER TACHO- METER TAN WIRE TEMP WHT WIRE YEL WIRE

3 4 5 PNK PNK WIRE 389 419 VSS OUTPUT MIL CTRL 420 1807 PPL PPL BRAKE SIG SERIAL DATA 440 1225 1224 IGN FEED RANGE SIG "B" RANGE SIG "A" A/C REQUEST SIG A/C SYSTEM BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRN WIRE BRN/WHT WIRE BULKHEAD GROMMET TOWARD IGNITION SW) CYLINDER 2 CYLINDER 1 CYLINDER 5 CYLINDER 3 CYLINDER 4 CYLINDER 6 DISTRIBUTOR (TOP REAR OF ENGINE) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-BAT FUSE 6 EGR VALVE CTRL ELECTRONIC BRAKE CONTROL MODULE FEED FUEL PUMP PRIME CONNECTOR (TAPED TO FUEL PUMP RELAY BREAKOUT) GROUND GRY WIRE HIGH VOLTAGE COIL WIRE HOT AT ALL TIMES HOT IN RUN I-3 FUSE 9 I/P FUSE BLOCK (BEHIND DASH PANEL) (BODY BUILDER INSTALLED) IGN FEED IGNITION IGNITION COIL (TOP RIGHT SIDE OF ENGINE) IGNITION CONTROL MODULE (RIGHT TOP OF ENGINE, AT IGNITION COIL) LT BLU/WHT WIRE ORG/ WIRE PCS SOL (HI) INPUT SPD SENS SIG INPUT SPD SENS RTN TIMING CTRL SIG PCS SOL (LO) VCM GROUND VCM GROUND GROUND 451 451 470 PNK 6 7 8 9 10 11 12 13 14 15 WIRE PNK IGN FEED WIRE PNK WIRE PPL PPL (ENGINE HARN, 18 CM FROM BREAKOUT TO BULKHEAD CONN) PPL FUEL LEVEL PRESSURE SWITCH IN RANGE SIG "C" RED WIRE RED/ BLK WIRE RED/BLK WIRE SHIFT INTERLOCK SYSTEM PPL SPARK PLUGS TIMING CONTROL RETURN TIMING CONTROL SIGNAL) TORQUE CONVERTER CLUTCH, STOP LAMP SWITCH (AT BRAKE PEDAL SUPPPORT) TRANSMISSION INPUT SPEED SENSOR (ON LEFT SIDE OF TRNASMISSION, NEAR THE MIDDLE) WHT WIRE WHT/ BLU WIRE WHT/BLK WIRE

14 15 16 PPL PPL 2-3 SHIFT SOL CTRL ANTI-LOCK BRAKE SYSTEM BLK WIRE BLU/WHT WIRE BRN WIRE BRN/WHT WIRE CAM POSIT SENS RTN FUEL LEV SIGNAL PPL CAM POSIT SENS SIG CAMSHAFT POSITION (CMP) SENSOR (INTERNAL TO DISTRIBUTOR) DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/ WHT WIRE DK GRN/WHT WIRE FUEL TANK PRESSURE SENSOR (AT FUEL TANK) 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 BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WHT/ WIRE LT GRN 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 1 2 WIRE PNK PNK 30 31 WIRE PNK WIRE PNK/BLK WIRE PPL PPL CKP SENS RTN VSS RTN VSS SIG PPL PPL PPL/WHT WIRE PURGE VENT RED/BLK WIRE TAN WIRE TAN/ WHT WIRE TAN/WHT WIRE VEHICLE SPEED OUT VEHICLE SPEED SENSOR (VSS) (LEFT SIDE OF TRANSMISSION) WHT PPL/ WIRE WHT WIRE YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOLENOID 14 15 16 PPL PPL 2-3 SHIFT SOLENOID AUTOMATIC TRANSMISSION (A/T) (IF EQUIPPED) (REAR OF ENGINE) BLK WIRE BLU WIRE BLU/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 EXHAUST GAS RECIRCULATION (EGR) VALVE (TOP FRONT OF ENGINE) 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 (BEHIND DASH PANEL) (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 1 2 WIRE PNK PNK 30 31 WIRE PNK PNK PNK PNK 1 2 3 4 WIRE PNK PNK WIRE PNK WIRE PNK/BLK WIRE PPL PPL 8 9 10 11 12 13 14 15 16 17 PPL/WHT WIRE PRESSURE CONTROL SOLENOID (PCS) RED WIRE RED/BLK WIRE REV TAN WIRE TAN/WHT WIRE TCC PWM SOLENOID TRANSMISSION FLUID TEMPERATURE SENSOR TRANSMISSION RANGE (TR) PRESSURE SWITCH ASSEMBLY WHT PPL/ WIRE WHT TAN/ WIRE WHT WIRE YEL WIRE YEL/BLK WIRE

5 6 7 8 9 10 11 12 PNK PNK WIRE A/C COMPRESSOR HIGH PRESSURE CUT-OFF SWITCH (REAR OF A/C COMPRESSOR) BLK WIRE BRN WIRE BRN/WHT WIRE DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ENG BAT FUSE 10 ENGINE COOLANT TEMPERATURE (ECT) SENSOR (TOP FRONT OF ENGINE) FROM ECT SENSOR BREAKOUT) FROM TP SENSOR BREAKOUT) FUEL GAUGE FUEL SENDER, FUEL PUMP (TOP OF FUEL TANK) GAUGES FUSE 8 GRY WIRE HOT AT ALL TIMES HOT IN RUN, START I/P FUSE BLOCK (BEHIND DASH PANEL) (BODY BUILDER INSTALLED) INSTRUMENT CLUSTER LT BLU/WHT WIRE LT GRN WIRE MAP MASS AIR FLOW (MAF) SENSOR (MOUNTED IN FRESH AIR INTAKE, BEHIND AIR FILTER BOX) NCA WIRE ORG/ WIRE PNK 10 11 12 13 14 15 16 17 WIRE PNK 5 6 WIRE PNK PNK PNK PNK 1 2 3 4 WIRE PNK WIRE PPL PPL 1 2 PPL 8 9 RED WIRE RED/BLK WIRE REF LO REF LO TEMP REF THROTTLE POSITION (TP) SENSOR (ON THROTTLE BODY, TOP OF ENGINE) SERVICE ENGINE SOON INDICATOR SPEEDO- METER TACHO- METER TAN WIRE TRANS FUSE 17 WHT WIRE YEL WIRE

389 419 VSS OUTPUT MIL CTRL 440 1225 1224 IGN FEED RANGE SIG "B" RANGE SIG "A" 5 6 7 8 9 PNK PNK WIRE A/C REQUEST SIG A/C SW IN A/C SYSTEM BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE CLUTCH PEDAL POSITION SWITCH (TOP OF CLUTCH PEDAL SUPPORT) CLUTCH SIG CYLINDER 1 CYLINDER 4 CYLINDER 5 CYLINDER 3 CYLINDER 6 CYLINDER 7 CYLINDER 2 CYLINDER 8 DISTRIBUTOR (TOP REAR OF ENGINE) DK BLU WIRE DK BLU/ WHT WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-BAT FUSE 6 EGR CTRL ELECTRONIC BRAKE CONTROL MODULE FEED IGNITION FUEL PUMP PRIME CONNECTOR (TAPED TO FUEL PUMP RELAY BREAKOUT) GROUND GRY WIRE HIGH VOLTAGE COIL WIRE HOT AT ALL TIMES HOT IN RUN I-3 FUSE 9 I/P FUSE BLOCK (BEHIND DASH PANEL) (BODY BUILDER INSTALLED) IGN FEED IGNITION COIL (TOP RIGHT SIDE OF ENGINE) IGNITION CONTROL MODULE (RIGHT TOP OF ENGINE, AT IGNITION COIL) LT BLU/WHT WIRE ORG/ WIRE PCS SOL (HI) INPUT SPD SENS SIG INPUT SPD SENS RTN TIMING CTRL SIG PCS SOL (LO) VCM GND VCM GND GND 451 451 470 PNK IGN FEED WIRE PNK WIRE PPL PPL 1 2 PPL 2 4 5 16 DATA LINK CONNECTOR (DLC) (BELOW DASH, NEAR STEERING COLUMN) PPL ANTI-LOCK BRAKE SYSTEM PPL FUEL LEV PPL PPL 420 1807 BRAKE SIG SERIAL DATA RANGE SIG "C" RED WIRE RED/ BLK WIRE RED/BLK WIRE RETURN CONTROL TIMING SIGNAL CONTROL TIMING SPARK PLUGS TORQUE CONVERTER CLUTCH, STOP LAMP SWITCH (AT BRAKE PEDAL SUPPORT) TRANSMISSION INPUT SPEED SENSOR (LEFT SIDE OF TRANSMISSION, NEAR THE MIDDLE) WHT WIRE WHT/BLK WIRE

1226 1225 TR SWITCH C TR SWITCH B TR SWITCH A 27 28 29 30 31 PPL A/C SYSTEM ANTILOCK BRAKES SYSTEM AUTOMATIC TRANSMISSION BATTERY BLK WIRE BLK/WHT WIRE BLU WIRE BLU/WHT WIRE BRN (OR LT BLU) WIRE BRN WIRE BRN/WHT WIRE CLOSURE SIGNAL BOOST SENSOR SIG PRESS CTRL SOL VLV LO DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DK PNK/ PNK WIRE ECT SIGNAL GRN WIRE GRY WIRE GRY/BLK WIRE LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/WHT WIRE ORG/ WIRE ORG/BLK WIRE PNK PNK PPL 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 WIRE PNK WIRE PNK/BLK WIRE POWERTRAIN CONTROL MODULE (PCM) (LEFT SIDE OF DRIVER'S ISLAND ON RELAY BRACKET) PPL PPL CKP SEN GRD A/C REQUEST SIG PPL TCC/ABS BRAKE SW STOPLAMP SWITCH CRIUSE SET/COAST SIG 20 84 PPL/WHT WIRE PRESSURE CONTROL SOLENOID VALVE RANGE MODE SELECTOR RED WIRE RED/BLK WIRE RESUME SENSOR GND SET- SOLENOID VALVE 1-2 SHIFT SOLENOID VALVE 2-3 SHIFT SOLENOID VALVE TCC PWM SOLID STATE SPEED CONTROL SWITCH TAN WIRE TAN/BLK WIRE TIMING STEPPER MTR (LOW) TIMING STEPPER MTR (LOW) TOWARD BREAKOUT FOR GRNERATOR CONNECTOR) TRANSMISSION OUTPUT SPEED SENSOR (LEFT SIDE OF TRANS- MISSION, NEAR THE MIDDLE) TRANSMISSION SPEED INPUT TRANSMISSION TEMPERATURE SENSOR WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE