GMC Suburban C2500 (1985-1999) i/p fuse block Wiring diagrams

1-2 SHIFT SOL 1-2 SHIFT SOLENOID 2-3 SHIFT SOL 2-3 SHIFT SOLENOID A/T ISS SENS HI IN A/T ISS SENS IN A/T ISS SENS LO IN A/T ISS SENSOR OUT ACCELERATOR PEDAL POSITION MODULE (PART OF ACCELERATOR PEDAL) APP 1 SIGNAL IN APP 2 SIGNAL IN APP 3 SIGNAL IN AUTOMATIC TRANSMISSION AUTOMATIC TRANSMISSION INPUT SHAFT SPEED SENSOR (LEFT FRONT OF TRANSMISSION) BATTERY IN BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRAKE FUSE 18 BRAKE SWITCH ASSEMBLY (ON BRAKE PEDAL BRACKET) BRAKE SWITCH IN BRN WIRE BRN/WHT WIRE CLASS II DATA DK BLU WIRE DK GRN WIRE ECM-B FUSE ECT SENSOR IN ENGINE COOLANT TEMP SENSOR (NEAR THERMOSTAT HOUSING) FRONT WHEEL LOCK FUEL PUMP, OIL PRESS SWITCH/ SENDER, FUEL PUMP RELAY GAUGES FUSE 4 GROUND GRY WIRE GRY/BLK WIRE HI PPL HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START HOT IN RUN OR START UNDERHOOD FUSE/RELAY CENTER ECM 1 FUSE HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK IGNITION IN INSTRUMENT CLUSTER LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MALFUNCTION INDICATOR LAMP MIL CONTROL ORG/ WIRE PCM GROUND PCS SOL HI OUT PCS SOL LO OUT PNK PNK WIRE PNK WIRE POWER POWERTRAIN CONTROL MODULE (RIGHT SIDE OF DASH NEAR BLOWER MOTOR) PPL PPL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) PPL/WHT WIRE PRESS CTRL SOLENOID LO RED WIRE RED/BLK WIRE SENSOR GROUND STOP/HAZ FUSE 1 STOPLAMP SWITCH IN TAN WIRE TAN/WHT WIRE TCC PWM SOL TCC PWM SOLENOID TFT SENSOR IN TRANS FLUID TEMP SENSOR TRANS FUSE 20 TRANS RANGE "A" TRANS RANGE "B" TRANS RANGE "C" TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANS RANGE SWITCHES TRANSFER CASE CIRCUIT PNK WIRE TRANSFER CASE, AXLE SWITCHES TURN/ HAZARD SWITCH, CHIME MODULE VEHICLE SPEED SENSOR VEHICLE SPEED SENSOR (VSS) ADAPTOR VEHICLE SPEED SENSOR BUFFER (RIGHT SIDE OF DASH) VSS HI IN VSS IN VSS LO IN VSS OUT WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOL 2-3 SHIFT SOL 3-2 SHIFT SOL TRANS FLUID TEMP (TFT) SENSOR BLK WIRE BLK/WHT WIRE BLK/YEL WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE DATA LINK CONNECTOR (BELOW LEFT SIDE OF DASH) DK BLU WIRE DK BLU/WHT WIRE ECM I FUSE ECM-B FUSE ENGINE COOLANT TEMPERATURE (ECT) SENSOR (TOP FRONT OF ENGINE) GAGES FUSE 4 GRY WIRE HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK INSTRUMENT CLUSTER LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE ORG/ WIRE PNK WIRE POWERTRAIN CONTROL MODULE (PCM) (UNDER RIGHT END OF DASH) PPL PPL PNK WIRE PPL/WHT WIRE PRESSURE CONTROL SOLENOID RANGE MODE SELECTOR RED WIRE RED/BLK WIRE SERVICE ENGINE SOON SPEED SENSOR (LEFT REAR SIDE OF TRANSMISSION) TAN WIRE TCC/STOPLAMP SWITCH (ON BRAKE PEDAL BRACKET) THROTTLE POSITION SENSOR (RIGHT SIDE OF TBI) TRANS FUSE 20 TRANSMISSION TRANSMISSION INPUT SHAFT SPEED SENSOR (FRONT OF TRANSMISSION) UNDERHOOD FUSE/RELAY CENTER VEHICLE SPEED SENSOR BUFFER (UNDER RIGHT END OF DASH) WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

AUTOMATIC TRANSFER CASE CONTROL MODULE (BEHIND LEFT SIDE OF DASH) AUX PWR FUSE 7 BLK WIRE BLK/WHT WIRE DATA LINK CONNECTOR (DLC) (UNDER LEFT SIDE OF DASH, LEFT OF STEERING COLUMN) DIAG ENABLE DIESEL GASOLINE DK GRN WIRE ELECTRONIC BRAKE CONTROL MODULE (EBCM) (ON LEFT SIDE OF ENGINE COMPT) EXCEPT LUXURY HOT AT ALL TIMES I/P FUSE BLOCK INFLATABLE RESTRAINT SENSING, DIAGNOSTIC MODULE (UNDER DRIVER'S SEAT CARPET) ORG/ WIRE PPL PPL DATA CLSS 2 PROG ENABLE RADIO REMOTE CONTROL DOOR LOCK RECEIVER (BEHIND CENTER OF DASH) SERIAL DATA TAN WIRE TAN/WHT WIRE UART DATA VEHICLE CONTROL MODULE (VCM) (ON LEFT SIDE OF ENGINE COMPT) VEHICLE INTERFACE UNIT

BLK WIRE DK GRN/WHT WIRE HOT IN RUN OR START TURN/BU FUSE 16 I/P FUSE BLOCK LT GRN WIRE PARK/ NEUTRAL POSITION SWITCH (LEFT SIDE OF TRANSMISSION) PNK WIRE TCC/STOPLAMP SWITCH (OPEN W/ BRAKE APPLIED) (TOP OF BRAKE PEDAL) TRANSFER CASE CONTROL MODULE (UNDER DASH ON STEERING COLUMN SUPPORT BRACKET) TURN/ HAZARD SWITCH PNK WIRE W/ ELECTRIC SHIFT TRANSFER CASE

5 CM FROM TRANSFER CASE BREAK-OUT) BLK WIRE BLK/WHT WIRE BRN WIRE CONVENIENCE CENTER DIESEL FROM ENGINE HARN BREAK-OUT) FRONT AXLE ACTUATOR FRONT AXLE SWITCH FUSE 24 GASOLINE GRY WIRE GRY/BLK WIRE HOT IN PARK OR HEAD HOT IN RUN I/P FUSE BLOCK ILLUM FUSE 14 INDICATOR LT BLU WIRE POWERTRAIN CONTROL MODULE (REARWARD OF LEFT SHOCK TOWER) RED WIRE TRANSFER CASE MODE SELECTOR ILLUMINATION LAMP TRANSFER CASE RELAY TRANSFER CASE SWITCH (TOP LEFT OF TRANSFER CASE) TRANSFER CASE SYNCHRONIZER

5 CM FROM TRANSFER CASE BREAK-OUT) BLK WIRE BLK/WHT WIRE BRN WIRE CONVENIENCE CENTER DIESEL FROM ENGINE HARN BREAK-OUT) FRONT AXLE ACTUATOR FRONT AXLE SWITCH FUSE 24 GASOLINE GRY WIRE GRY/BLK WIRE HOT IN PARK OR HEAD HOT IN RUN I/P FUSE BLOCK ILLUM FUSE 14 INDICATOR LT BLU WIRE POWERTRAIN CONTROL MODULE (REARWARD OF LEFT SHOCK TOWER) RED WIRE TRANSFER CASE MODE SELECTOR ILLUMINATION LAMP TRANSFER CASE RELAY TRANSFER CASE SWITCH (TOP LEFT OF TRANSFER CASE) TRANSFER CASE SYNCHRONIZER

5 CM FROM TRANSFER CASE BREAK-OUT) BLK WIRE BLK/WHT WIRE BRN WIRE CONVENIENCE CENTER DIESEL FROM ENGINE HARN BREAK-OUT) FRONT AXLE ACTUATOR FRONT AXLE SWITCH FUSE 24 GASOLINE GRY WIRE GRY/BLK WIRE HOT IN PARK OR HEAD HOT IN RUN I/P FUSE BLOCK ILLUM FUSE 14 INDICATOR LT BLU WIRE POWERTRAIN CONTROL MODULE (REARWARD OF LEFT SHOCK TOWER) RED WIRE TRANSFER CASE MODE SELECTOR ILLUMINATION LAMP TRANSFER CASE RELAY TRANSFER CASE SWITCH (TOP LEFT OF TRANSFER CASE) TRANSFER CASE SYNCHRONIZER

16 PPL 6 7 8 9 10 PNK WIRE AUTOMATIC TRANSMISSION INPUT SHAFT SPEED SENSOR (LEFT SIDE OF TRANSMISSION) BALANCE FUEL PUMP (ON INSIDE LEFT FRAME RAIL NEAR FRONT OF REAR TANK) BLK (OR WIRE BLK WIRE BLK/WHT WIRE BLU WIRE BLU/WHT WIRE BRN WIRE BRN/WHT WIRE CONVENIENCE CENTER (UNDER LEFT SIDE OF DASH) DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE FUEL GAUGE FUEL PUMP BALANCE MODULE (INSIDE LEFT SIDE OF FRAME RAIL) FUEL PUMP BALANCE RELAY (ON FUEL PUMP BALANCE MODULE) FUEL PUMP, SENDER (IN FUEL TANK) FUEL TANK PRESSURE SENSOR (IN FUEL TANK) GAUGES FUSE 4 GRN WIRE GROUND GRY WIRE HOT IN OFF, RUN OR START HOT IN RUN OR START I/P FUSE BLOCK IGN E FUSE INPUT INSTRUMENT CLUSTER INTAKE AIR TEMPERATURE SENSOR (IN AIR INTAKE DUCT) LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE M/T ONLY MASS AIR FLOW SENSOR (IN AIR INTAKE DUCT) OUTPUT TO GAUGE PNK (TAILLAMP EXTENSION HARN, 6 CM FROM THE FUEL PUMP HARN BREAKOUT) WIRE PNK IGNITION WIRE PNK PNK PNK WIRE PNK WIRE PPL PPL/WHT WIRE PRIMARY TANK FUEL LVL SIG RED WIRE RED/BLK WIRE RELAY CTRL SECON TANK FUEL LVL SIG SECONDARY FUEL GAUGE SENDER (IN FUEL TANK) SERVICE ENGINE SOON INDICATOR SPEEDOMETER TACHOMETER TAN WIRE TAN/BLK WIRE THROTTLE POSITION SENSOR (ON THROTTLE BODY ASSEMBLY) TRANS FUSE 20 UNDERHOOD FUSE-RELAY CENTER UPSHIFT LAMP W/ DUAL FUEL TANK W/O DUAL FUEL TANK W/ DUAL FUEL TANKS W/O DUAL FUEL TANK W/O DUAL FUEL TANK W/ DUAL FUEL TANKS W/O DUAL FUEL TANKS W/ DUAL FUEL TANK WHT (OR WIRE WHT WIRE YEL WIRE YEL/BLK WIRE

A/C REQUEST SIGNAL AIR CONDITIONING SYSTEM AIR INLET VLV MTR CTLR 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) 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 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 FUEL PUMP RLY CTRL 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 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 BRAKE INPUT INPUT SW INPUT IGNITION COIL (TOP LEFT REAR OF ENGINE) IGNITION COIL DRIVER (LEFT REAR SIDE 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 SERIAL INPUT DATA SIG ORG/ 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 STOPLAMP/ VCM SENSOR CLUTCH SIG INPUT SWITCH INPUT 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) UNDERHOOD FUSE-RELAY CENTER VEHICLE CONTROL MODULE (VCM) (LEFT SIDE OF ENGINE COMPT) VSS SIG OUT VSS SIG OUT CHECK ENG LP CTRL 389 419 WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

28 29 30 31 32 PPL 5 VOLT REF ACCELERATOR PEDAL POSITION (APP) MODULE (PART OF ACCELERATOR PEDAL) BLK WIRE BLU WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE CLUTCH PEDAL POSITION (CPP) SWITCH (M/T ONLY) (TOP OF CLUTCH PEDAL BRACKET) CMP SIG DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE DK PNK WIRE ECM 1 FUSE ELECTRONIC BRAKE CONTROL MODULE (ON LEFT SIDE OF ENGINE COMPT) GRN WIRE GRY WIRE HIGH RES SIG HOT AT ALL TIMES HOT IN HOT IN RUN OR START I/P FUSE BLOCK INJECTION TIMING STEPPER MOTOR (TOP RIGHT FRONT OF ENGINE) LT BLU WIRE LT GRN WIRE LT PPL NCA WIRE OPTICAL FUEL TEMPERATURE SENSOR (ON TOP OF FUEL INJECTION PUMP) ORG/ WIRE ORG/BLK WIRE PNK PNK 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 WIRE PNK PNK 9 10 WIRE PNK PNK PNK WIRE PNK PNK PPL WIRE PNK PNK WIRE PNK WIRE PNK/BLK WIRE POWER DISTRIBUTION SYSTEM PPL PPL (OR BRN/WHT) WIRE RED WIRE RED/BLK WIRE RUN WIRE SENS GRD STOP- LAMP SWITCH (ON TOP OF BRAKE PEDAL) STOP/HAZ FUSE 1 TAN WIRE TAN/BLK WIRE TRANS FUSE 20 UNDERHOOD FUSE-RELAY CENTER WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE