GMC Rally G2500 (1985-1995) nca Wiring diagrams

4.3L AND 5.7L 4.3L AND 5.7L ONLY 5.7L HD ONLY 452 455 PPL 5.7L HD 7.4L 7.4L ONLY AIR CONDITION- ING SYSTEM BLK WIRE BLK/RED WIRE BLK/WHT WIRE BLK/YEL WIRE BRN WIRE BRN/WHT WIRE CRUISE CONTROL SYSTEM CRUISE SIGNAL DIAGNOSTIC TEST TP SENSOR SIGNAL INJECTOR 1 CONTROL DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DK GRN/YEL WIRE ECM I FUSE ECM B FUSE ECT SIGNAL EGR CONTROL GOVERNOR CONTROL EGR ELECTONIC VACUUM REGULATOR SOLENIOD VALVE (TOP RIGHT SIDE OF ENGINE) EVAPORATIVE CANISTER PURGE CONTROL SOLENOID (TOP RIGHT FRONT OF ENGINE) EXHAUST GAS RECIRCULATION VALVE SOLENOID (TOP RIGHT SIDE OF ENGINE) FUEL PUMP RELAY CTRL PCS LOW FUEL PUMP SIGNAL MAP SIGNAL FUSE BLOCK GRY WIRE GRY/RED WIRE HOT AT ALL TIMES HOT IN RUN, BULB TEST OR START IC BYPASS SENSOR GROUND SENSOR GROUND TFT SIGNAL IDLE AIR CONTROL UNIT (RIGHT SIDE OF THROTTLE BODY) IDLE SPEED ACTUATOR CONTROL SOLENOID (NO LOCATION AVAILABLE) KNOCK SIGNAL EGR PINTLE POSITION SIGNAL LINEAR EGR VACUUM REGULATOR SOLENOID VALVE (ABOVE RIGHT ROCKER COVER) LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE NCA WIRE ORG/ WIRE ORG/BLK WIRE OXYGEN SENSOR (IN EXHAUST MANIFOLD) OXYGEN SENSOR GROUND PNK 23 24 PPL WIRE PNK WIRE PNK/BLK WIRE POWERTRAIN CONTROL MODULE (UNDER DRIVER'S SEAT) PPL PPL 21 22 PPL/WHT WIRE RANGE SIGNAL A INPUT SPEED SIGNAL HIGH INPUT SPEED SIGNAL LOW RANGE SIGNAL B RANGE SIGNAL C MIL CONTROL RED WIRE RED/BLK WIRE TAN WIRE TAN/BLK WIRE TAN/WHT WIRE THROTTLE BODY FUEL INJECTOR #1 (TOP OF THROTTLE BODY UNIT) THROTTLE BODY FUEL INJECTOR #2 (TOP OF THROTTLE BODY UNIT) TRANS FUSE TRANSMISSION INPUT SPEED SENSOR (NO LOCATION) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

3 121 PNK WIRE ACCY AUXILIARY FUSE BLOCK BLK WIRE BLK/RED WIRE BLK/YEL WIRE BRAKE FUSE BRN WIRE BRN/WHT WIRE BULB TEST DISTRIBUTOR (CENTER REAR OF ENGINE) DK BLU WIRE DK GRN/WHT WIRE ENGINE COOLANT TEMPERATURE SENSOR (ON INTAKE MANIFOLD) FUSE BLOCK GAGES FUSE GRY WIRE HOT AT ALL TIMES HOT IN RUN HOT IN RUN, BULB TEST OR START IGNITION COIL (TOP RIGHT REAR OF ENGINE) IGNITION SWITCH INSTRUMENT CLUSTER KNOCK SENSOR (LEFT REAR OF ENGINE, NEAR OIL PRESSURE SENDER) LOCK OFF LT BLU/WHT WIRE LT GRN WIRE MALFUNCTION (SERVICE ENGINE SOON) INDICATOR MANIFOLD ABSOLUTE PRESSURE SENSOR (ABOVE VALVE COVER) NCA WIRE ORG/BLK WIRE PNK PPL 23 24 WIRE PNK WIRE PNK/BLK WIRE PNK/WHT WIRE PPL PPL 21 22 PPL 3 4 PPL/WHT WIRE RED WIRE RED/BLK WIRE RUN WIRE TACHOMETER TEST LEAD TAN/BLK WIRE TCC/BRAKE SWITCH (ON BRAKE PEDAL SUPPORT BRACKET) THROTTLE POSITION SENSOR (ON THROTTLE BODY) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

3 121 PNK WIRE 4.3L AND 7.4L 5.7L ACCY ALT FUSE BLK WIRE BLK/RED WIRE BLK/YEL WIRE BRN WIRE BRN/WHT WIRE BULB TEST DISTRIBUTOR (CENTER REAR OF ENGINE) DK BLU WIRE DK GRN/WHT WIRE ENGINE COOLANT TEMPERATURE SENSOR (TOP FRONT OF ENGINE) FUSE BLOCK GRY WIRE HOT AT ALL TIMES HOT IN RUN, BULB TEST OR START IGNITION COIL (TOP RIGHT REAR OF ENGINE) IGNITION SWITCH INSTRUMENT CLUSTER KNOCK SENSOR (LEFT REAR OF ENGINE, NEAR OIL PRESSURE SENDER) KNOCK SENSOR MODULE (TOP RIGHT SIDE OF ENGINE) LOCK OFF LT BLU/WHT WIRE LT GRN WIRE MALFUNCTION (SERVICE ENGINE SOON) INDICATOR MANIFOLD ABSOLUTE PRESSURE SENSOR (ABOVE VALVE COVER) NCA WIRE ORG/ WIRE PNK 25 26 WIRE PNK WIRE PNK/BLK WIRE PPL PPL 2 3 4 PPL 23 24 PPL/WHT WIRE PROVISIONS FOR TACHOMETER RED WIRE RED/BLK WIRE RUN WIRE TAN/BLK WIRE TCC/BRAKE SWITCH (ON BRAKE PEDAL SUPPORT BRACKET) THROTTLE POSITION SENSOR (ON THROTTLE BODY) TRANS FUSE WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

1 2 PPL 1-2 SHIFT SOLENIOD 2-3 SHIFT SOLENIOD 4.3L 5.7L AND 7.4L B/H CONN BLK WIRE BLK/WHT WIRE BLK/YEL WIRE BRN WIRE DATA LINK CONNECTOR (BEHIND LEFT SIDE OF SHIPPING PANEL) DK BLU WIRE DK GRN/WHT WIRE ECM BAT FUSE ELECTRONIC 4-SPEED AUTOMATIC OVERDRIVE TRANSMISSION FUEL PUMP AND SENDER (IN FUEL TANK) FUEL PUMP OIL PRESSURE SWITCH (TOP REAR OF ENGINE) FUEL PUMP PRIME CONNECTOR (NO LOCATION AVAILABLE) FUEL PUMP RELAY (LOWER LEFT SIDE OF SHIPPING PANEL) FUSE BLOCK GRY WIRE HEATED OXYGEN SENSOR (IN EXHAUST MANIFOLD) HOT AT ALL TIMES LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE ORG/ WIRE OXYGEN SENSOR (IN EXHAUST MANIFOLD) PNK WIRE PNK/BLK WIRE PPL PPL/WHT WIRE PRESSURE CONTROL SOLENOID RANGE MODE SELECTOR RED WIRE RED/BLK WIRE SOLENOID TORQUE CONVERTER CLUTCH TRANS- MISSION TEMP SENSOR VEHICLE SPEED SENSOR (LEFT REAR OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (BEHIND RIGHT SIDE OF I/P) WHT/BLK WIRE YEL/BLK WIRE

5.7L 7.4L 7.4L ONLY AIR CONDITION- ING SYSTEM BLK WIRE BLK/RED WIRE BLK/WHT WIRE BLK/YEL WIRE BRN WIRE BRN/WHT WIRE DIAGNOSTIC TEST TP SENSOR SIGNAL INJECTOR 1 CONTROL DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DK GRN/YEL WIRE ECM I FUSE ECT SIGNAL EGR CONTROL EVAPORATIVE CANISTER PURGE CONTROL SOLENOID (TOP RIGHT SIDE OF ENGINE) EXHAUST GAS RECIRCULATION VALVE SOLENOID (TOP RIGHT SIDE OF ENGINE) FUEL PUMP RELAY CTRL PCS LOW FUEL PUMP SIGNAL MAP SIGNAL FUSE BLOCK GRY WIRE GRY/RED WIRE HOT IN RUN, BULB TEST OR START IC BYPASS SENSOR GROUND SENSOR GROUND TFT SIGNAL 470 455 PPL IDLE AIR CONTROL ACTUATOR (TOP REAR OF ENGINE) IDLE SPEED ACTUATOR CONTROL SOLENOID (NO LOCATION AVAILABLE) KNOCK SIGNAL EGR PINTLE POSITION SIGNAL LINEAR EGR VACUUM REGULATOR SOLENOID VALVE (TOP FRONT OF ENGINE) LT BLU/BLK WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE LT GRN/WHT WIRE NCA WIRE ORG/ WIRE OXYGEN SENSOR (IN EXHAUST MANIFOLD) OXYGEN SENSOR GROUND PNK 22 23 WIRE PNK RANGE SIGNAL A INPUT SPEED SIGNAL HIGH INPUT SPEED SIGNAL LOW WIRE PNK/BLK WIRE POWERTRAIN CONTROL MODULE (LEFT SIDE OF SHIPPING PANEL) PPL PPL 20 21 PPL/WHT WIRE RANGE SIGNAL B RANGE SIGNAL C MIL CONTROL RED WIRE RED/BLK WIRE TAN WIRE TAN/BLK WIRE TAN/WHT WIRE THROTTLE BODY FUEL INJECTOR #1 (TOP OF THROTTLE BODY UNIT) THROTTLE BODY FUEL INJECTOR #2 (TOP OF THROTTLE BODY UNIT) TRANSMISSION INPUT SPEED SENSOR (LEFT SIDE OF TRANSMISSION) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

3 121 PNK WIRE ACCY BLK WIRE BLK/RED WIRE BLK/YEL WIRE BRN WIRE BRN/WHT WIRE BULB TEST DISTRIBUTOR (CENTER REAR OF ENGINE) DK BLU WIRE DK GRN/WHT WIRE ENGINE COOLANT TEMPERATURE SENSOR (TOP FRONT OF ENGINE) FUSE BLOCK GAGES FUSE GRY WIRE HOT AT ALL TIMES HOT IN RUN, BULB TEST OR START IGNITION COIL (TOP RIGHT REAR OF ENGINE) IGNITION SWITCH INSTRUMENT CLUSTER KNOCK SENSOR (LEFT REAR OF ENGINE, NEAR OIL PRESSURE SENDER) LOCK OFF LT BLU/WHT WIRE LT GRN WIRE MALFUNCTION (SERVICE ENGINE SOON) INDICATOR MANIFOLD ABSOLUTE PRESSURE SENSOR (ABOVE VALVE COVER) NCA WIRE ORG/ WIRE PNK 22 23 WIRE PNK WIRE PNK/BLK WIRE PPL PPL 20 21 PPL 3 4 PPL/WHT WIRE PROVISIONS FOR TACHOMETER RED WIRE RED/BLK WIRE RUN WIRE TAN/BLK WIRE TCC/BRAKE SWITCH (ON BRAKE PEDAL SUPPORT BRACKET) THROTTLE POSITION SENSOR (ON THROTTLE BODY) TRANS FUSE WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOLENIOD 2-3 SHIFT SOLENIOD B/H CONN BLK WIRE BLK/WHT WIRE BLK/YEL WIRE BRN WIRE DATA LINK CONNECTOR (BEHIND LEFT SIDE OF SHIPPING PANEL) DK BLU WIRE DK GRN/WHT WIRE ELECTRONIC 4-SPEED AUTOMATIC OVERDRIVE TRANSMISSION FUEL PUMP AND SENDER (IN FUEL TANK) FUEL PUMP FUSE FUEL PUMP OIL PRESSURE SWITCH (TOP REAR OF ENGINE) FUEL PUMP PRIME CONNECTOR (TOP OF COWL) FUEL PUMP RELAY (LOWER LEFT SIDE OF SHIPPING PANEL) FUSE BLOCK GRY WIRE HOT AT ALL TIMES LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE ORG/ WIRE PNK WIRE PNK/BLK WIRE PPL PPL 3 4 PPL/WHT WIRE PRESSURE CONTROL SOLENOID RANGE MODE SELECTOR RED WIRE RED/BLK WIRE SOLENOID TAN/BLK WIRE TORQUE CONVERTER CLUTCH TRANS- MISSION TEMP SENSOR VEHICLE SPEED SENSOR (LEFT REAR OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (BEHIND RIGHT SIDE OF I/P) WHT/BLK WIRE YEL/BLK WIRE

3 121 PNK WIRE 4.3L 5.7L ACCY ALT FUSE BLK WIRE BLK/RED WIRE BLK/WHT WIRE BRN/WHT WIRE BULB TEST DISTRIBUTOR (TOP REAR OF ENGINE) DK BLU WIRE DK GRN/WHT WIRE FUEL PUMP AND SENDER (IN FUEL TANK) FUEL PUMP OIL PRESSURE SWITCH (TOP REAR OF ENGINE) FUEL PUMP PRIME CONNECTOR FUEL PUMP RELAY (LOWER LEFT SIDE OF SHIPPING PANEL) FUSE BLOCK GRY WIRE HOT AT ALL TIMES HOT IN RUN, BULB TEST OR START IGNITION COIL (TOP OF ENGINE NEAR DISTRIBUTOR) IGNITION SWITCH INSTRUMENT CLUSTER KNOCK SENSOR (RIGHT SIDE OF ENGINE) KNOCK SENSOR MODULE (TOP RIGHT SIDE OF ENGINE) LOCK OFF LT GRN/BLK WIRE MALFUNCTION (SERVICE ENGINE SOON) INDICATOR NCA WIRE ORG/ WIRE OXYGEN SENSOR (IN EXHAUST MANIFOLD) HEATED OXYGEN SENSOR (IN EXHAUST MANIFOLD) PNK PPL PPL WIRE PNK WIRE PNK/BLK WIRE PPL PPL/WHT WIRE PROVISIONS FOR TACHOMETER RED WIRE RUN WIRE TAN/BLK WIRE VEHICLE SPEED SENSOR (LEFT REAR OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (BEHIND RIGHT SIDE OF I/P) WHT WIRE

"TRANS" LAMP 1-2 SHIFT SOL 2-3 SHIFT SOL TCC SOL 2-3 SHIFT SOL CTRL 1-2 SHIFT SOL CTRL DIAGNOSTIC TEST A/C INPUT BRAKE SIGNAL TCC CONTROL PPL ACCY AIR CONDI- TIONING SYSTEM ALT FUSE B/H BATTERY FEED BLK WIRE BLK/WHT WIRE BLK/YEL WIRE BLU WIRE BRN WIRE BULB TEST COLD ADVANCE FAST IDLE TEMPERATURE SWITCH (RIGHT REAR OF ENGINE) COLD ADVANCE SOLENOID (TOP FRONT OF ENGINE) DATA LINK CONNECTOR (BEHIND LEFT SIDE SHIPPING DIODE (BEHIND GENERATOR) DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE ECM BAT FUSE ECM CRANK FUSE ELECTRONIC 4-SPEED AUTOMATIC OVERDRIVE TRANSMISSION ENGINE SPEED SIGNAL SENSOR GROUND TP SENSOR INPUT FAST IDLE SOLENOID (TOP LEFT SIDE OF ENGINE) FUEL HEATER (TOP REAR OF ENGINE) FUEL SHUT- OFF SOLENOID (TOP FRONT OF ENGINE) FUSE BLOCK FUSIBLE LINK (20 GA-RUST) FUSIBLE LINKS GLOW PLUG CONTROLLER (LEFT SIDE OF ENGINE) GLOW PLUG WAIT LAMP GRY WIRE GRY/BLK WIRE GRY/RED WIRE HOT AT ALL TIMES HOT AT ALL TIMES FUSIBLE LINK HOT IN CRANK HOT IN RUN, BULB TEST OR START INPUTS INSTRUMENT CLUSTER LEFT BANK GLOW PLUGS LOCK OFF LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE ORG/ WIRE ORG/BLK WIRE PANEL) PCS HI PCS LO IGNITION PNK RANGE SIGNAL A RANGE SIGNAL B RANGE SIGNAL C WIRE PNK WIRE PNK/BLK WIRE PPL PRESSURE CONTROL SOLENOID RANGE MODE SELECTOR RED WIRE RED/BLK WIRE RIGHT BANK GLOW PLUGS RUN WIRE SERVICE TRANS OUTPUT SERIAL DATA SYSTEM GROUND SYSTEM GROUND 452 416 SENSOR GROUND 5 VOLTS REF TAN/BLK WIRE TCC/BRAKE SWITCH (ON BRAKE PEDAL SUPPORT) TRANS FLUID TEMP SIG MAP SENS TRANS FUSE TRANS- MISSION FLUID TEMP (TFT) SENSOR TRANSMISSION CONTROL MODULE (TCM) (BEHIND LEFT SIDE OF SHIPPING PANEL) TRANSMISSION INPUT SPEED SENSOR (LEFT SIDE OF TRANSMISSION) VEHICLE SPEED INPUT TRANS INPUT SPD LO TRANS INPUT SPD HI VEHICLE SPEED SENSOR (REAR OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (UNDER RIGHT SIDE OF I/P) VEHICLE SPD OUTPUT VSS WATER IN FUEL INDICATOR WATER-IN FUEL SENSOR (TOP REAR OF ENGINE) WHT WIRE WHT/BLK WIRE YEL/BLK WIRE

ACCY ALT FUSE BLK WIRE BULB TEST COLD ADVANCE FAST IDLE TEMPERATURE SWITCH (RIGHT REAR OF ENGINE) COLD ADVANCE SOLENOID (TOP FRONT OF ENGINE) DK BLU WIRE FAST IDLE SOLENOID (TOP LEFT SIDE OF ENGINE) FUEL HEATER (TOP REAR OF ENGINE) FUEL SHUT- OFF SOLENOID (TOP FRONT OF ENGINE) FUSE BLOCK FUSIBLE LINK (12 GA- RUST) (NO LOCATION AVAILABLE) FUSIBLE LINK (20 GA- RUST) (ON STARTER MOTOR) FUSIBLE LINKS GLOW PLUG CONTROLLER (LEFT SIDE OF ENGINE) GLOW PLUG WAIT LAMP GROUND (NO LOCATION AVAILABLE) HOT AT ALL TIMES HOT IN RUN OR START HOT IN START INSTRUMENT CLUSTER LEFT BANK GLOW PLUGS LOCK OFF LT GRN/BLK WIRE NCA WIRE ORG/ WIRE ORG/BLK WIRE PNK WIRE PNK/BLK WIRE RED WIRE RIGHT BANK GLOW PLUGS RUN WIRE WATER IN FUEL INDICATOR WATER-IN FUEL SENSOR (TOP REAR OF ENGINE) YEL/BLK WIRE