Chevrolet Cab & Chassis C3500 (1989-2000) transmissions system Wiring diagrams

ABS FUSE ABS IND. BATTERY PUMP MOTOR GROUND BLK WIRE BLK/WHT WIRE BRAKE FUSE 18 BRAKE IND BRAKE PRESSURE WARNING SWITCH (UNDERSIDE OF EBCM) BRAKE SW OUTPUT BRN WIRE DAYTIME RUNNING LAMP (DRL) MODULE (BEHIND LEFT SIDE OF DASH) DK GRN WIRE ELECTRONIC BRAKE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) ENGINE CONTROLS SYSTEM FRONT AXLE ACTUATOR (ON RIGHT REAR OF FRONT DRIVE AXLE) FUSE/RELAY BLOCK (LEFT REAR OF ENGINE COMPT) GAUGES FUSE 4 HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) IGNITION ABS IND GROUND BRAKE SW INPUT INSTRUMENT CLUSTER LEFT FRONT WHEEL SPEED SENSOR LT BLU WIRE LT GRN WIRE LT GRN/BLK WIRE M/T NEAR BREAKOUT TO TRANSFER CASE RELAY) PNK WIRE PPL PPL DATA LINK CONNECTOR (DLC) (LEFT OF STEERING COLUMN) PPL PPL 1807 680 PPL SERIAL DATA PPL/WHT WIRE RED WIRE RIGHT FRONT WHEEL SPEED SENSOR SENSOR LOW SENSOR LOW SENSOR HIGH SENSOR HIGH 830 872 STOPLAMP SWITCH (TOP OF BRAKE PEDAL) TAN WIRE TAN/WHT WIRE TRANSFER CASE CONTROL MODULE (ON STEERING COLUMN SUPPORT BRACKET) TRANSMISSIONS SYSTEM VEHICLE CONTROL MODULE (VCM) (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED SENSOR (VSS) (LEFT SIDE OF TRANSMISSION/ TRANSFER CASE) VEHICLE SPEED SIG VSS VSS SIG BRAKE LAMP IND OUT SERIAL DATA LINE BRAKE IND INPUT EBCM GROUND YEL WIRE YEL/BLK WIRE

ABS FUSE ABS IND. BATTERY PUMP MOTOR GROUND BLK WIRE BLK/WHT WIRE BRAKE FUSE 18 BRAKE IND BRAKE PRESSURE WARNING SWITCH (UNDERSIDE OF EBCM) BRN WIRE DAYTIME RUNNING LAMP (DRL) MODULE (BEHIND LEFT SIDE OF DASH) DK GRN WIRE ELECTRONIC BRAKE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) ENGINE CONTROLS SYSTEM FRONT AXLE ACTUATOR (ON RIGHT REAR OF FRONT DRIVE AXLE) FUSE/RELAY BLOCK (LEFT REAR OF ENGINE COMPT) GAUGES FUSE 4 HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) IGNITION ABS IND GROUND BRAKE SW INPUT INSTRUMENT CLUSTER LEFT FRONT WHEEL SPEED SENSOR LT BLU WIRE LT GRN WIRE M/T NEAR BREAKOUT TO TRANSFER CASE RELAY) PNK WIRE POWERTRAIN CONTROL MODULE (PCM) (BEHIND RIGHT SIDE OF DASH) PPL PPL DATA LINK CONNECTOR (DLC) (LEFT OF STEERING COLUMN) PPL PPL 1807 680 PPL SERIAL DATA RED WIRE RIGHT FRONT WHEEL SPEED SENSOR SENSOR LOW SENSOR LOW SENSOR HIGH SENSOR HIGH 830 872 SERIAL DATA STOPLAMP SWITCH (TOP OF BRAKE PEDAL) TAN WIRE TAN/WHT WIRE TRANSFER CASE CONTROL MODULE (ON STEERING COLUMN SUPPORT BRACKET) TRANSMISSIONS SYSTEM VSS OUT VSS SIG BRAKE LAMP IND OUT SERIAL DATA LINE BRAKE IND INPUT EBCM GROUND YEL WIRE YEL/BLK WIRE

ABS FUSE ABS IND. BATTERY PUMP MOTOR GROUND BLK WIRE BLK/WHT WIRE BRAKE FUSE 18 BRAKE IND BRAKE PRESSURE WARNING SWITCH (UNDERSIDE OF EBCM) BRAKE SW OUTPUT BRN WIRE DAYTIME RUNNING LAMP (DRL) MODULE (BEHIND LEFT SIDE OF DASH) DK GRN WIRE ELECTRONIC BRAKE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) ENGINE CONTROLS SYSTEM FRONT AXLE ACTUATOR (ON RIGHT REAR OF FRONT DRIVE AXLE) FUSE/RELAY BLOCK (LEFT REAR OF ENGINE COMPT) GAUGES FUSE 4 HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) IGNITION ABS IND GROUND BRAKE SW INPUT INSTRUMENT CLUSTER LEFT FRONT WHEEL SPEED SENSOR LT BLU WIRE LT GRN WIRE LT GRN/BLK WIRE M/T NEAR BREAKOUT TO TRANSFER CASE RELAY) PNK WIRE PPL PPL DATA LINK CONNECTOR (DLC) (LEFT OF STEERING COLUMN) PPL PPL 1807 680 PPL SERIAL DATA PPL/WHT WIRE RED WIRE RIGHT FRONT WHEEL SPEED SENSOR SENSOR LOW SENSOR LOW SENSOR HIGH SENSOR HIGH 830 872 STOPLAMP SWITCH (TOP OF BRAKE PEDAL) TAN WIRE TAN/WHT WIRE TRANSFER CASE CONTROL MODULE (ON STEERING COLUMN SUPPORT BRACKET) TRANSMISSIONS SYSTEM VEHICLE CONTROL MODULE (VCM) (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED SENSOR (VSS) (LEFT SIDE OF TRANSMISSION/ TRANSFER CASE) VEHICLE SPEED SIG VSS VSS SIG BRAKE LAMP IND OUT SERIAL DATA LINE BRAKE IND INPUT EBCM GROUND YEL WIRE YEL/BLK WIRE

4.3L W/ A/C ON SIGNAL IN BRAKE SW TO PCM AIR CONDITION- ING SYSTEM BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE COOLANT TEMP. SENSOR CRUISE CONTROL SYSTEM CRUISE IND REG GRD DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DLC THROTTLE POSITION SENSOR IN LO SIDE INJ A ECM-I MINI FUSE EGR VALVE SOLENOID (4.3/5.0/5.7L EGR VALVE SOLENOID TRANS SHIFT 3/2 SOLENOID ELEC FUEL PUMP IN MAP SENSOR IN EMISSIONS) (RIGHT SIDE OF ENGINE) ENG-I MINI FUSE EVAP CANISTER PURGE CTRL EVAPORATIVE CANISTER PURGE SOLENOID (5.0, 5.7L W/ 4L60E, 4.3L W/ FUEL PUMP RELAY CTRL PCM TRANS FORCE MTR LO GRY WIRE GRY/BLK WIRE HOT IN RUN OR START IDLE AIR CONTROL UNIT (RIGHT REAR OF TBI UNIT) IGNITION BYPASS KNOCK SENSOR IN PINTLE POSITION SIGNAL LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE ORG/ WIRE OXYGEN SENSOR LO PCM TO TRANS TEMP SENSOR PCM TRANS RANGE A TRANS INPUT SPEED IN HI TRANS INPUT SPEED IN LO PCM TRANS RANGE B PCM TRANS RANGE C MIL INDICATOR CTRL PCM TRANS SHIFT SOL B PCM TRANS SHIFT SOL A PNK WIRE POWERTRAIN CONTROL MODULE (UNDER RIGHT SIDE OF I/P) PPL PPL 1 2 3 4 PPL 23 24 PPL/WHT WIRE RED WIRE RED/BLK WIRE TAN WIRE TAN/BLK WIRE TAN/WHT WIRE TCC CLUTCH CTRL TCC CLUTCH CTRL THROTTLE BODY FUEL INJECTOR #1 (TOP OF THROTTLE BODY UNIT) THROTTLE BODY FUEL INJECTOR #2 (TOP OF THROTTLE BODY UNIT) TRANSMISSION INPUT SHAFT SPEED SENSOR TRANSMISSIONS SYSTEM UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) WHT DK GRN/ WIRE WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

4.3L W/ A/C ON SIGNAL IN BRAKE SW TO PCM AIR CONDITION- ING SYSTEM BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE COOLANT TEMP. SENSOR CRUISE CONTROL SYSTEM CRUISE IND REG GRD DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DLC THROTTLE POSITION SENSOR IN LO SIDE INJ A ECM-I MINI FUSE EGR VALVE SOLENOID (4.3/5.0/5.7L EGR VALVE SOLENOID TRANS SHIFT 3/2 SOLENOID ELEC FUEL PUMP IN MAP SENSOR IN EMISSIONS) (RIGHT SIDE OF ENGINE) ENG-I MINI FUSE EVAP CANISTER PURGE CTRL EVAPORATIVE CANISTER PURGE SOLENOID (5.0, 5.7L W/ 4L60E, 4.3L W/ FUEL PUMP RELAY CTRL PCM TRANS FORCE MTR LO GRY WIRE GRY/BLK WIRE HOT IN RUN OR START IDLE AIR CONTROL UNIT (RIGHT REAR OF TBI UNIT) IGNITION BYPASS KNOCK SENSOR IN PINTLE POSITION SIGNAL LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE ORG/ WIRE OXYGEN SENSOR LO PCM TO TRANS TEMP SENSOR PCM TRANS RANGE A TRANS INPUT SPEED IN HI TRANS INPUT SPEED IN LO PCM TRANS RANGE B PCM TRANS RANGE C MIL INDICATOR CTRL PCM TRANS SHIFT SOL B PCM TRANS SHIFT SOL A PNK WIRE POWERTRAIN CONTROL MODULE (UNDER RIGHT SIDE OF I/P) PPL PPL 1 2 3 4 PPL 23 24 PPL/WHT WIRE RED WIRE RED/BLK WIRE TAN WIRE TAN/BLK WIRE TAN/WHT WIRE TCC CLUTCH CTRL TCC CLUTCH CTRL THROTTLE BODY FUEL INJECTOR #1 (TOP OF THROTTLE BODY UNIT) THROTTLE BODY FUEL INJECTOR #2 (TOP OF THROTTLE BODY UNIT) TRANSMISSION INPUT SHAFT SPEED SENSOR TRANSMISSIONS SYSTEM UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) WHT DK GRN/ WIRE WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

A/C REQUEST SIGNAL AIR CONDITIONING SYSTEM AIR INLET VLV MTR CTLR AUTOMATIC AUTOMATIC TRANSFER CASE SHIFT CONTROLLER BLK WIRE BLK/WHT WIRE BLU WIRE BLU/WHT WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE CLUTCH PEDAL POSITION (CPP) SWITCH (AT TOP OF CLUTCH PEDAL BRACKET) CPP SW INPUT FOUR WHL DR SIG LO CRUISE CTRL SIG ENG 23 24 CRUISE CONTROL MODULE (LEFT REAR OF ENGINE COMPT, ON FIREWALL) DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH, LEFT SIDE OF STEERING COLUMN) DISTRIBUTOR DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ELECTRONIC BRAKE CONTROL MODULE (EBCM) (ON LEFT SIDE OF ENGINE COMPT) ELECTRONIC VARIABLE ORIFICE/ PASSLOCK CONTROL MODULE (CENTER OF DASH) FORCE MOTOR FEED TRANS INPUT SPEED RTN TRANS INPUT SPEED SIG EST OUTPUT SIG FORCE MOTOR RETURN GROUND GROUND SENSOR GROUND FUEL LEVEL INPUT SWITCH SIGNAL FUEL PUMP PRIME CONNECTOR (LEFT REAR OF ENG COMPT) FUEL PUMP RELAY GRN WIRE GROUND GRY WIRE GRY/BLK WIRE HIGH VOLTAGE COIL WIRE HOT AT ALL TIMES UNDERHOOD FUSE- RELAY CENTER ECMB FUSE HOT IN RUN I/P FUSE BLOCK IGN INPUT BRAKE SW INPUT INPUT IGNITION IGNITION COIL (TOP RIGHT REAR OF ENGINE) IGNITION CONTROL MODULE (RIGHT SIDE REAR OF ENGINE) IGNITION FEED IGN TIMING SIG. IGN COIL OUT IGNITION PRESSURE SWITCH INPUT PRESSURE SWITCH INPUT LT BLU/BLK WIRE LT BLU/WHT WIRE LT DK VSS INPUT SERIAL DATA SIG MANUAL OR SELECTABLE ORG/ WIRE PNK 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 WIRE PNK IGNITION FOUR WHL DR SIG EGR VLV GROUND WIRE PNK PNK PNK WIRE PNK WIRE PPL PPL (OR PPL A/T M/T PPL PPL PPL PPL 420 OR PPL/WHT WIRE PRESSURE SWITCH INPUT RADIO RED WIRE RED/BLK WIRE SENSOR RETURN SHIFT IND LP OUT EGR VLV FEED SPEED SENSOR SPEED SENSOR INPUT STOPLAMP/ CLUTCH SWITCH INPUT VCM SIG STOPLAMP SWITCH (TOP OF BRAKE PEDAL) SWITCH SIGNAL TAN/BLK WIRE TRANSFER CASE CONTROL MODULE (UNDER DASH ON STEERING COLUMN SUPPORT BRACKET) TRANSFER CASE SWITCH (LEFT TOP OF TRANSFER CASE) TRANSMISSIONS SYSTEM UNDERHOOD FUSE-RELAY CENTER VEHICLE CONTROL MODULE (VCM) (LEFT SIDE OF ENGINE COMPT) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

4.3L W/ A/C ON SIGNAL IN BRAKE SW TO PCM AIR CONDITION- ING SYSTEM BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE COOLANT TEMP. SENSOR CRUISE CONTROL SYSTEM CRUISE IND REG GRD DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DLC THROTTLE POSITION SENSOR IN LO SIDE INJ A ECM-I MINI FUSE EGR VALVE SOLENOID (4.3/5.0/5.7L EGR VALVE SOLENOID TRANS SHIFT 3/2 SOLENOID ELEC FUEL PUMP IN MAP SENSOR IN EMISSIONS) (RIGHT SIDE OF ENGINE) ENG-I MINI FUSE EVAP CANISTER PURGE CTRL EVAPORATIVE CANISTER PURGE SOLENOID (5.0, 5.7L W/ 4L60E, 4.3L W/ FUEL PUMP RELAY CTRL PCM TRANS FORCE MTR LO GRY WIRE GRY/BLK WIRE HOT IN RUN OR START IDLE AIR CONTROL UNIT (RIGHT REAR OF TBI UNIT) IGNITION BYPASS KNOCK SENSOR IN PINTLE POSITION SIGNAL LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE ORG/ WIRE OXYGEN SENSOR LO PCM TO TRANS TEMP SENSOR PCM TRANS RANGE A TRANS INPUT SPEED IN HI TRANS INPUT SPEED IN LO PCM TRANS RANGE B PCM TRANS RANGE C MIL INDICATOR CTRL PCM TRANS SHIFT SOL B PCM TRANS SHIFT SOL A PNK WIRE POWERTRAIN CONTROL MODULE (UNDER RIGHT SIDE OF I/P) PPL PPL 1 2 3 4 PPL 23 24 PPL/WHT WIRE RED WIRE RED/BLK WIRE TAN WIRE TAN/BLK WIRE TAN/WHT WIRE TCC CLUTCH CTRL TCC CLUTCH CTRL THROTTLE BODY FUEL INJECTOR #1 (TOP OF THROTTLE BODY UNIT) THROTTLE BODY FUEL INJECTOR #2 (TOP OF THROTTLE BODY UNIT) TRANSMISSION INPUT SHAFT SPEED SENSOR TRANSMISSIONS SYSTEM UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) WHT DK GRN/ WIRE WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOL 2-3 SHIFT SOL 12 7 8 9 10 VSS SIG VSS RTN GROUND IGN VSS SIG 1226 1225 RANGE MODE SEL C RANGE MODE SEL B RANGE MODE SEL A 13 14 15 VSS HI VSS OUTPUT VSS OUTPUT 27 28 29 30 31 PPL A/C REQUEST SIG A/C SYSTEM A/T FLUID PRESSURE (TFP) MANUAL VALVE POSITION SWITCH ANTI-LOCK BRAKES SYSTEM AUTOMATIC TRANSMISSION BLK WIRE BLK/WHT WIRE BLU WIRE BLU/WHT WIRE BRN WIRE BRN/WHT (M/T) WIRE BRN/WHT WIRE CRUISE CONTROL SYSTEM DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DK PNK WIRE ECT TEMP SENS IN GRN WIRE GRY WIRE GRY/BLK WIRE INLINE GENDER ADAPTER INTAKE MAN AIR TEMP SENS APP 2 SIG GLOW PLUG RELAY FORCE MTR LOW LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT PNK WIRE LT PPL LT PPL PPL MAP SENS INPUT FORCE MTR HI NCA WIRE ORG/ WIRE ORG/BLK WIRE OTHERS PNK PNK 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) (BEHIND RIGHT SIDE OF DASH, NEAR BLOWER MOTOR) PPL PPL (A/T) BRAKE SW IN BRAKE SWITCH INPUT CRUISE CTRL SW ENGAGE PPL (OR BRN/WHT) WIRE PPL/WHT WIRE PRESSURE CONTROL SOLENOID VALVE RADIO, EVO/ PASSLOCK CONTROL MODULE, TRANSFER CASE CONTROL MODULE RED WIRE RED/BLK WIRE SENSOR GND TAN WIRE TAN/BLK WIRE TIMING STEPPER MTR (HIGH) 3 MODE CRUISE PPL SENSOR GND SENSOR GND APP 1 SIG TIMING STEPPER MTR (LOW) TIMING STEPPER MTR (LOW) TORQUE CONVERTER CLUTCH PULSE WDTH MOD SOL TRANSMISSION SPEED INPUT TRANSMISSION TEMP INPUT TRANSMISSION TEMPERATURE SENSOR TRANSMISSIONS SYSTEM VEHICLE SPEED SENSOR (LEFT SIDE OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (BEHIND RIGHT SIDE OF DASH) VSS VSS LO HI WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

AIR CONDITION- ING SYSTEM BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE COOLANT TEMP. SENSOR DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DLC THROTTLE POSITION SENSOR IN LO SIDE INJ A EGR VALVE SOLENOID ELEC FUEL PUMP IN MAP SENSOR IN ENG-I MINI FUSE EVAP CANISTER PURGE CTRL EVAPORATIVE CANISTER PURGE SOLENOID (RIGHT SIDE OF ENGINE) FUEL PUMP RELAY CTRL PCM TRANS FORCE MTR LO GRY WIRE GRY/BLK WIRE HOT IN RUN OR START IDLE AIR CONTROL UNIT (RIGHT REAR OF TBI UNIT) IGNITION BYPASS KNOCK SENSOR IN LINEAR EGR POSITION IN LINEAR EGR REGULATOR SOLENOID VALVE (LEFT REAR OF ENGINE) LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE ORG/ WIRE OXYGEN SENSOR LO PCM TO TRANS TEMP SENSOR PCM TRANS RANGE A TRANS INPUT SPEED IN HI TRANS INPUT SPEED IN LO PCM TRANS RANGE B PCM TRANS RANGE C MIL INDICATOR CTRL PCM TRANS SHIFT SOL B PCM TRANS SHIFT SOL A PNK PNK PNK 25 26 27 WIRE PNK WIRE POWERTRAIN CONTROL MODULE (UNDER RIGHT SIDE OF I/P) PPL PPL 1 2 3 4 PPL 22 23 PPL/WHT WIRE RED WIRE RED/BLK WIRE TAN WIRE TAN/BLK WIRE TAN/WHT WIRE THROTTLE ACTUATOR SOL CTRL TCC CLUTCH CTRL A/C ON SIGNAL IN BRAKE SW TO PCM THROTTLE BODY FUEL INJECTOR #1 (TOP OF THROTTLE BODY UNIT) THROTTLE BODY FUEL INJECTOR #2 (TOP OF THROTTLE BODY UNIT) TRANSMISSION INPUT SHAFT SPEED SENSOR (LEFT SIDE OF TRANS- MISSION) TRANSMISSIONS SYSTEM WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE