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

** (FRONT OF LEFT CYLINDER HEAD) (REAR OF CYLINDER HEAD) ** (RIGHT FRAME RAIL, NEAR BATTERY) ** (RIGHT SIDE OF RADIATOR SUPPORT) (RIGHT REAR OF ENGINE) ** WITH SCHOOLBUS EQUIPMENT BATTERY (GASOLINE ENGINES) BLK BLK WIRE BLK WIRE BLK/ WHT WIRE BLK/WHT WIRE CONTROLLER CONVENIENCE CENTER DATA LINK CONN- ECTOR DAYTIME RUNNING LAMP MODULE DAYTIME TRANSMISSION RUNNING LAMP RELAY RANGE INDICATOR LAMP FUEL CYCLE MODULE EGR ELECTRONIC VACUUM REGULATOR SOLENOID VALVE ENGINE ENGINE DATA LINK CONNECTOR TRANSMISSION CONTROL MODULE COOLANT LEVEL SENSOR FUEL PUMP FUEL PUMP RELAY LEFT (OR REAR ) BATTERY ** LEFT HIGH BEAM HEADLAMP LEFT HIGH/ LOW HEADLAMP LEFT HORN LEFT TURN/ PARK LAMP ASSEMBLY NOT USED PANEL DIMMER SWITCH WASHER PUMP I/P CLUSTER PARK BRAKE SWITCH POWERTRAIN CONTROL MODULE (PCM) PROVISIONS PROVISIONS FOR RIGHT SIDE MARKER FOR LEFT SIDE MARKER RIGHT (OR FRONT ) BATTERY RIGHT HIGH BEAM HEADLAMP RIGHT HIGH/ LOW HEADLAMP RIGHT HORN RIGHT TURN/ PARK LAMP ASSEMBLY STARTER RELAY TAN WIRE VEHICLE SPEED SENSOR BUFFER FUEL HEATER VEHICLE SPEED SENSOR BUFFER KNOCK SENSOR SYSTEM MODULE HEATED OXYGEN SENSOR W/ AUTOMATIC TRANSMISSION W/ AUTOMATIC TRANSMISSIONS W/ DAYTIME RUNNING LIGHTS W/ DIESEL ENGINE W/ DIESEL ENGINES W/ GASOLINE ENGINES W/ SCHOOLBUS EQUIPMENT WATER- IN-FUEL SENSOR GLOW PLUG WIPER MOTOR

A/C COMPRESSOR A/C COMPRESSOR PRESSURE CYCLING SWITCH BATTERY BLK WIRE BLK/ WHT WIRE BLK/WHT WIRE BLOWER MOTOR BLOWER RELAY BRAKE SHIFT INTERLOCK RELAY BRAKE/ TRANSMISSION SHIFT INTERLOCK SOLENOID VEHICLE SPEED SENSOR BUFFER BUS BAR GROUND CANADA ONLY CIGARETTE LIGHTER CRUISE CONTROL MODULE DATA LINK CONN- ECTOR FUEL PUMP RELAY DAYTIME RUNNING LAMPS MODULE DAYTIME RUNNING LAMPS RELAY DK GRN WIRE EGR ELECTRONIC VACUUM REGULATOR VALVE SOLENOID FLOW SWITCH (BRAKES) FUEL PUMP HEATER CONTROL LAMP IN LINE DIODE INSTRUMENT CLUSTER LEFT HIGH BEAM HEADLAMP LEFT HORN LEFT LOW BEAM HEADLAMP LEFT PARK AND TURN LAMP LEFT PARK LAMP LEFT SIDE MARKER LAMP LEFT TAIL STOP AND TURN LAMP LICENSE LAMP GROUND (FROM BODY BUILDER) POWER DOOR LOCK RELAY POWERTRAIN CONTROL MODULE (PCM) PROVISIONS FOR CLEARANCE LAMPS LEFT POWER WINDOW SWITCH RADIO RIGHT HIGH BEAM HEADLAMP RIGHT HORN RIGHT LOW BEAM HEADLAMP RIGHT PARK AND TURN LAMP RIGHT PARK LAMP SAFETY BELT RETRACTOR SWITCH AUDIO ALARM MODULE TAN WIRE TAN/WHT WIRE WINDSHIELD WASHER PUMP LIGHT SWITCH WINDSHIELD WIPER MOTOR MODULE

** (RIGHT FRAME RAIL, NEAR BATTERY) A/C COMPRESSOR CLUTCH AUXILLIARY COOLING FAN AUDIO ALARM MODULE AUTO APPLY PARK BRAKE DATA LINK CONN- ECTOR POWERTRAIN CONTROL MODULE (PCM) AUXILLIARY COOLING FAN COOLANT PRESSURE SWITCH BATTERY BLK WIRE BLK/WHT WIRE BRAKE TRANSMISSION SHIFT INTERLOCK SOLENOID BRAKE/ TRANSMISSION SHIFT INTERLOCK RELAY CRUISE CONTROL MODULE DAYTIME RUNNING LAMPS MODULE DAYTIME RUNNING LAMPS RELAY FUEL PUMP FUEL PUMP RELAY G# N/A (AT LEFT REAR FRAME RAIL) G# N/A (AT LEFT SHIPPING PANEL) G#S N/A (IN FORWARD LAMPS HARNESS) HEADLAMP DIMMER SWITCH I/P CLUSTER LEFT HIGH BEAM HEADLAMP LEFT HIGH/LOW BEAM HEADLAMP PROVISIONS FOR LEFT SIDE MARKER LAMP PROVISIONS FOR RIGHT SIDE MARKER LAMP RIGHT HIGH BEAM HEADLAMP RIGHT HIGH/LOW BEAM HEADLAMP TAN WIRE TRANSMISSION RANGE INDICATOR LAMP VEHICLE SPEED SENSOR BUFFER W/ DAYTIME RUNNING LIGHTS WHT/ BLK WIRE WIPER/ WASHER SWITCH

BLK WIRE GRN WIRE HEADLAMP DIMMER SWITCH HI BEAM INDICATOR HI LO HOT AT ALL TIMES LEFT HEADLAMP ASSEMBLY LO HI LIGHT SWITCH LT GRN WIRE LT INSTRUMENT CLUSTER OFF OFF HEAD HEAD PARK PARK RIGHT HEADLAMP ASSEMBLY HI TAN WIRE YEL WIRE

BLK WIRE BRN WIRE DAYTIME RUNNING LAMP INDICATOR DAYTIME RUNNING LAMPS MODULE (IN I/P HARNESS) DAYTIME RUNNING LAMPS RELAY (IN I/P HARNESS) DK BLU/WHT WIRE DK GRN/YEL WIRE FUSE BLOCK GRN WIRE HEAD PARK HEADLAMP DIMMER SWITCH HEADLIGHT SWITCH ASSEMBLY HI BEAM INDICATOR HI LO HORN/DM FUSE HOT AT ALL TIMES HOT IN RUN HTR FUSE INSTRUMENT CLUSTER LEFT HEADLAMP ASSEMBLY LT GRN WIRE LT GRN/BLK WIRE OFF OFF HEAD ORG/ WIRE PARK PARK BRAKE WARNING SWITCH (AT PARK BRAKE, UNDER LEFT SIDE OF I/P) PROVISIONS FOR FOG LAMPS RIGHT HEADLAMP ASSEMBLY TAN WIRE TAN/WHT WIRE WHT WIRE YEL WIRE

BLK WIRE GRN WIRE HEADLAMP DIMMER SWITCH HI BEAM INDICATOR HI LO HOT AT ALL TIMES LEFT HIGH BEAM HEADLAMP ASSEMBLY LEFT LOW BEAM HEADLAMP ASSEMBLY LIGHT SWITCH LT GRN WIRE LT INSTRUMENT CLUSTER OFF OFF HEAD HEAD PARK PARK RIGHT HIGH BEAM HEADLAMP ASSEMBLY RIGHT LOW BEAM HEADLAMP ASSEMBLY TAN WIRE YEL WIRE

BLK WIRE DAYTIME RUNNING LAMP INDICATOR DAYTIME RUNNING LAMPS MODULE (BEHIND LEFT SIDE OF I/P) DAYTIME RUNNING LAMPS RELAY (BEHIND LEFT SIDE OF I/P, ABOVE STEERING COLUMN) DK BLU/WHT WIRE DRL FUSE FUSE BLOCK GAUGES FUSE GRN WIRE HEAD PARK HEADLAMP DIMMER SWITCH HEADLIGHT SWITCH ASSEMBLY HI BEAM INDICATOR HI LO HOT AT ALL TIMES HOT IN RUN OR START IGNITION LAMP FEED HI BEAM FEED HI BEAM INDICATOR OUTPUT TO RELAY GROUND INSTRUMENT CLUSTER LEFT HIGH BEAM HEADLAMP LEFT LOW BEAM HEADLAMP LT GRN WIRE LT GRN/BLK WIRE OFF OFF HEAD ORG/ WIRE PARK PARK BRAKE WARNING SWITCH (ON PARK BRAKE SUPPORT BRACKET) PNK/BLK WIRE PPL PPL BULB CHECK RIGHT HIGH BEAM HEADLAMP RIGHT LOW BEAM HEADLAMP TAN WIRE WHT WIRE YEL WIRE

BLK WIRE GRN WIRE HEADLAMP DIMMER SWITCH HI BEAM INDICATOR HI LO HOT AT ALL TIMES INSTRUMENT CLUSTER LEFT HEADLAMP ASSEMBLY HI LEFT LOWER HEAD- LAMP (W/ HPR) LIGHT SWITCH LT GRN WIRE OFF OFF HEAD HEAD PARK PARK RIGHT HEADLAMP ASSEMBLY LO HI RIGHT LOWER HEAD- LAMP (W/ HPR) TAN WIRE YEL WIRE

BLK WIRE BLU WIRE BRN WIRE DAYTIME RUNNING LAMP CUTOFF RELAY DAYTIME RUNNING LAMP INDICATOR DAYTIME RUNNING LAMPS MODULE (IN I/P HARNESS) DAYTIME RUNNING LAMPS RELAY (IN I/P HARNESS) DK BLU/WHT WIRE DK GRN/YEL WIRE GRN WIRE HEAD PARK HEADLAMP DIMMER SWITCH HEADLIGHT SWITCH ASSEMBLY HI BEAM INDICATOR HI LO HORN/DM FUSE HOT AT ALL TIMES HOT IN RUN OR START FUSE BLOCK HTR FUSE INSTRUMENT CLUSTER LEFT HEADLAMP ASSEMBLY LEFT LOWER HEADLAMP (W/ HPR) LT GRN WIRE LT GRN/BLK WIRE OFF OFF HEAD ORG/ WIRE PARK PARK BRAKE WARNING SWITCH (AT PARK BRAKE, UNDER LEFT SIDE OF I/P) PROVISIONS FOR FOG LAMPS RIGHT HEADLAMP ASSEMBLY RIGHT LOWER HEADLAMP (W/ HPR) TAN WIRE TAN/WHT WIRE WHT WIRE YEL 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