GMC Pickup K2500 (1985-2000) fuel pump prime conn- ector Wiring diagrams

3-2 SHIFT SOLENOID ALL EXCEPT 5.7L W/ BLK WIRE BLK/WHT WIRE BRN OR TAN/BLK WIRE BRN WIRE DATA LINK CONNECTOR (UNDER LEFT SIDE OF I/P) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-B MINI FUSE ELECTRONIC 4-SPEED AUTOMATIC OVERDRIVE TRANSMISSION FUEL PUMP AND SENDER FUEL PUMP OIL PRESSURE SWITCH (TOP REAR OF ENGINE NEAR DISTRIBUTOR) FUEL PUMP PRIME CONN- ECTOR FUEL PUMP RELAY (UNDERHOOD FUSE/RELAY CENTER) GRY WIRE HEATED OXYGEN SENSOR (IN EXHAUST Y-PIPE) HOT AT ALL TIMES HOT IN RUN OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) INSTRUMENT CLUSTER LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE OIL PRESS IN ONLY ORG/ WIRE PNK WIRE PPL PPL/WHT WIRE PRESSURE CONTROL SOLENOID RANGE MODE SELECTOR RED WIRE RED/BLK WIRE SHIFT SOLE- NOID 1-2 SHIFT SOLENOID 2-3 SOLENOID TACH IN TAN WIRE TAN/BLK BRN OR WIRE TAN/BLK WIRE TORQUE CONVERTER CLUTCH TRANS FUSE 20 TRANS- MISSION TEMP SENSOR UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT REAR SIDE OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (UNDER RIGHT END OF I/P) VSS IN WHT WIRE WHT/BLK WIRE YEL/BLK WIRE

4.3L ONLY BLK WIRE BLK/WHT WIRE BRN WIRE DATA LINK CONNECTOR (UNDER LEFT SIDE OF I/P) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-B MINI FUSE FUEL PUMP AND SENDER FUEL PUMP OIL PRESSURE SWITCH (TOP REAR OF ENGINE NEAR DISTRIBUTOR) FUEL PUMP PRIME CONN- ECTOR FUEL PUMP RELAY (UNDERHOOD FUSE/RELAY CENTER) GRY WIRE HEATED OXYGEN SENSOR (IN EXHAUST Y-PIPE) HOT AT ALL TIMES IDLE SPEED CONTROL ACTUATOR SOLENOID (7.4L ONLY) (SIDE OF THROTTLE BODY UNIT) INSTRUMENT CLUSTER LT GRN/BLK WIRE OIL PRESS IN ORG/ WIRE PNK WIRE PPL PPL/WHT WIRE RED WIRE TACH IN TAN WIRE UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT REAR SIDE OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (UNDER RIGHT END OF I/P) VSS IN WHT WIRE WHT/BLK WIRE

3-2 SHIFT SOLENOID ALL EXCEPT 5.7L W/ BLK WIRE BLK/WHT WIRE BRN OR TAN/BLK WIRE BRN WIRE DATA LINK CONNECTOR (UNDER LEFT SIDE OF I/P) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-B MINI FUSE ELECTRONIC 4-SPEED AUTOMATIC OVERDRIVE TRANSMISSION FUEL PUMP AND SENDER FUEL PUMP OIL PRESSURE SWITCH (TOP REAR OF ENGINE NEAR DISTRIBUTOR) FUEL PUMP PRIME CONN- ECTOR FUEL PUMP RELAY (UNDERHOOD FUSE/RELAY CENTER) GRY WIRE HEATED OXYGEN SENSOR (IN EXHAUST Y-PIPE) HOT AT ALL TIMES HOT IN RUN OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) INSTRUMENT CLUSTER LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE OIL PRESS IN ONLY ORG/ WIRE PNK WIRE PPL PPL/WHT WIRE PRESSURE CONTROL SOLENOID RANGE MODE SELECTOR RED WIRE RED/BLK WIRE SHIFT SOLE- NOID 1-2 SHIFT SOLENOID 2-3 SOLENOID TACH IN TAN WIRE TAN/BLK BRN OR WIRE TAN/BLK WIRE TORQUE CONVERTER CLUTCH TRANS FUSE 20 TRANS- MISSION TEMP SENSOR UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT REAR SIDE OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (UNDER RIGHT END OF I/P) VSS IN WHT WIRE WHT/BLK WIRE YEL/BLK WIRE

3-2 SHIFT SOLENOID ALL EXCEPT 5.7L W/ BLK WIRE BLK/WHT WIRE BRN OR TAN/BLK WIRE BRN WIRE DATA LINK CONNECTOR (UNDER LEFT SIDE OF I/P) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-B MINI FUSE ELECTRONIC 4-SPEED AUTOMATIC OVERDRIVE TRANSMISSION FUEL PUMP AND SENDER FUEL PUMP OIL PRESSURE SWITCH (TOP REAR OF ENGINE NEAR DISTRIBUTOR) FUEL PUMP PRIME CONN- ECTOR FUEL PUMP RELAY (UNDERHOOD FUSE/RELAY CENTER) GRY WIRE HEATED OXYGEN SENSOR (IN EXHAUST Y-PIPE) HOT AT ALL TIMES HOT IN RUN OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) INSTRUMENT CLUSTER LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE OIL PRESS IN ONLY ORG/ WIRE PNK WIRE PPL PPL/WHT WIRE PRESSURE CONTROL SOLENOID RANGE MODE SELECTOR RED WIRE RED/BLK WIRE SHIFT SOLE- NOID 1-2 SHIFT SOLENOID 2-3 SOLENOID TACH IN TAN WIRE TAN/BLK BRN OR WIRE TAN/BLK WIRE TORQUE CONVERTER CLUTCH TRANS FUSE 20 TRANS- MISSION TEMP SENSOR UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT REAR SIDE OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (UNDER RIGHT END OF I/P) VSS IN WHT WIRE WHT/BLK WIRE YEL/BLK WIRE

BLK WIRE BLK/WHT WIRE BRN WIRE DATA LINK CONNECTOR (UNDER LEFT SIDE OF I/P) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-B MINI FUSE FUEL PUMP AND SENDER FUEL PUMP OIL PRESSURE SWITCH/SENDER (LEFT LOWER FRONT OF ENGINE, NEAR DAMPER) FUEL PUMP PRIME CONN- ECTOR FUEL PUMP RELAY (UNDERHOOD FUSE/RELAY CENTER) GRY WIRE HEAVY DUTY ELECTRONIC 4-SPEED AUTOMATIC OVERDRIVE TRANSMISSION HOT AT ALL TIMES HOT IN RUN OR START I/P FUSE BLOCK (BEHIND LEFT SIDE OF I/P) IDLE SPEED CONTROL ACTUATOR (ON THROTTLE BODY UNIT) INSTRUMENT CLUSTER LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE OIL PRESS IN ORG/ WIRE OXYGEN SENSOR (EXHAUST PIPE NEAR CROSSOVER) PNK WIRE PPL PPL/WHT WIRE PRESSURE CONTROL SOLENOID RANGE MODE SELECTOR RED WIRE RED/BLK WIRE SHIFT SOLENOID 1-2 SHIFT SOLENOID 2-3 TORQUE CONVERTER CLUTCH SOLENOID TACH IN TAN WIRE TRANS FUSE 20 TRANS- MISSION TEMP SENSOR UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT REAR SIDE OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (UNDER RIGHT END OF I/P) VSS IN WHT WIRE WHT/BLK WIRE YEL/BLK WIRE

4.3L ONLY BLK WIRE BLK/WHT WIRE BRN WIRE DATA LINK CONNECTOR (UNDER LEFT SIDE OF I/P) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE ECM-B MINI FUSE FUEL PUMP AND SENDER FUEL PUMP OIL PRESSURE SWITCH (TOP REAR OF ENGINE NEAR DISTRIBUTOR) FUEL PUMP PRIME CONN- ECTOR FUEL PUMP RELAY (UNDERHOOD FUSE/RELAY CENTER) GRY WIRE HEATED OXYGEN SENSOR (IN EXHAUST Y-PIPE) HOT AT ALL TIMES IDLE SPEED CONTROL ACTUATOR SOLENOID (7.4L ONLY) (SIDE OF THROTTLE BODY UNIT) INSTRUMENT CLUSTER LT GRN/BLK WIRE OIL PRESS IN ORG/ WIRE PNK WIRE PPL PPL/WHT WIRE RED WIRE TACH IN TAN WIRE UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT REAR SIDE OF TRANSMISSION) VEHICLE SPEED SENSOR BUFFER (UNDER RIGHT END OF I/P) VSS IN WHT WIRE WHT/BLK WIRE