GMC Suburban K2500 (1985-1999) lt blu Wiring diagrams

2-HI IND 4-HI IND 4-LO IND AUTO AUTOMATIC TRANSFER CASE CONTROL MODULE (BEHIND LEFT SIDE OF DASH) AUTOMATIC TRANSFER CASE SELECT SWITCH AWD IND AXLE CTRL AXLE SW B+ GND MOTOR FEED (CCW) MOTOR FEED (CW) BLK WIRE BLK/WHT WIRE BRAKE CONTROL BRN WIRE BRN/WHT WIRE DIESEL GASOLINE DK BLU/WHT WIRE DK GRN WIRE ENCODER LOGIC ENCODER MOTOR ASSEMBLY ENCODER SIG RTN FRONT AXLE ACTUATOR FRONT DRIVE SHAFT SPEED SENSOR REAR DRIVE SHAFT SPEED SENSOR FT SHAFT SPEED SIG FT SHAFT SPEED RTN FUSE 24 GAUGES FUSE 4 GRY WIRE GRY/BLK WIRE HEADLAMP/ DIMMER PANEL SWITCH PNK WIRE HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START HOT WITH HEADLIGHT SW IN PARK OR HEAD I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) ILLUM FUSE 14 ILLUMINATION LAMP (2) IND INSTRUMENT CLUSTER LOW SIG LT BLU WIRE LT BLU/BLK WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE NEUTRAL IND ORG/ WIRE PARK PARK/ NEUTRAL POSITION SWITCH PNK WIRE PNP SW-PARK SIG IN PPL PPL/WHT WIRE PWR RED WIRE RED/WHT WIRE REF SERVICE SHIFT MOTOR SOLID STATE STOP LAMP SWITCH T CASE FUSE 2 TAN WIRE TAN/BLK WIRE VEHICLE CONTROL MODULE (GASOLINE) (LEFT SIDE OF ENGINE COMPT) YEL WIRE YEL/BLK WIRE

2-HI IND 4-HI IND 4-LO IND AUTO AUTOMATIC TRANSFER CASE CONTROL MODULE (BEHIND LEFT SIDE OF DASH) AUTOMATIC TRANSFER CASE SELECT SWITCH AWD IND AXLE CTRL AXLE SW B+ GND MOTOR FEED (CCW) MOTOR FEED (CW) BLK WIRE BLK/WHT WIRE BRAKE CONTROL BRN WIRE BRN/WHT WIRE DIESEL GASOLINE DK BLU/WHT WIRE DK GRN WIRE ENCODER LOGIC ENCODER MOTOR ASSEMBLY ENCODER SIG RTN FRONT AXLE ACTUATOR FRONT DRIVE SHAFT SPEED SENSOR REAR DRIVE SHAFT SPEED SENSOR FT SHAFT SPEED SIG FT SHAFT SPEED RTN FUSE 24 GAUGES FUSE 4 GRY WIRE GRY/BLK WIRE HEADLAMP/ DIMMER PANEL SWITCH PNK WIRE HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START HOT WITH HEADLIGHT SW IN PARK OR HEAD I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) ILLUM FUSE 14 ILLUMINATION LAMP (2) IND INSTRUMENT CLUSTER LOW SIG LT BLU WIRE LT BLU/BLK WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE NEUTRAL IND ORG/ WIRE PARK PARK/ NEUTRAL POSITION SWITCH PNK WIRE PNP SW-PARK SIG IN PPL PPL/WHT WIRE PWR RED WIRE RED/WHT WIRE REF SERVICE SHIFT MOTOR SOLID STATE STOP LAMP SWITCH T CASE FUSE 2 TAN WIRE TAN/BLK WIRE VEHICLE CONTROL MODULE (GASOLINE) (LEFT SIDE OF ENGINE COMPT) YEL WIRE YEL/BLK WIRE

2-HI IND 4-HI IND 4-LO IND AUTO AUTOMATIC TRANSFER CASE CONTROL MODULE (BEHIND LEFT SIDE OF DASH) AUTOMATIC TRANSFER CASE SELECT SWITCH AWD IND AXLE CTRL AXLE SW B+ GND MOTOR FEED (CCW) MOTOR FEED (CW) BLK WIRE BLK/WHT WIRE BRAKE CONTROL BRN WIRE BRN/WHT WIRE DIESEL GASOLINE DK BLU/WHT WIRE DK GRN WIRE ENCODER LOGIC ENCODER MOTOR ASSEMBLY ENCODER SIG RTN FRONT AXLE ACTUATOR FRONT DRIVE SHAFT SPEED SENSOR REAR DRIVE SHAFT SPEED SENSOR FT SHAFT SPEED SIG FT SHAFT SPEED RTN FUSE 24 GAUGES FUSE 4 GRY WIRE GRY/BLK WIRE HEADLAMP/ DIMMER PANEL SWITCH PNK WIRE HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START HOT WITH HEADLIGHT SW IN PARK OR HEAD I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) ILLUM FUSE 14 ILLUMINATION LAMP (2) IND INSTRUMENT CLUSTER LOW SIG LT BLU WIRE LT BLU/BLK WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE NEUTRAL IND ORG/ WIRE PARK PARK/ NEUTRAL POSITION SWITCH PNK WIRE PNP SW-PARK SIG IN PPL PPL/WHT WIRE PWR RED WIRE RED/WHT WIRE REF SERVICE SHIFT MOTOR SOLID STATE STOP LAMP SWITCH T CASE FUSE 2 TAN WIRE TAN/BLK WIRE VEHICLE CONTROL MODULE (GASOLINE) (LEFT SIDE OF ENGINE COMPT) YEL WIRE YEL/BLK WIRE

AUXILIARY BATTERY RELAY BLK WIRE BLK/WHT WIRE BRN WIRE DIESEL FRONT AXLE ACTUATOR FUSE 24 GASOLINE GRY WIRE GRY/BLK WIRE HARN) HOT IN PARK OR HEAD HOT IN RUN I/P FUSE BLOCK (LEFT SIDE OF DASH, ILLUM FUSE 14 INDICATOR LT BLU WIRE M/T A/T POWERTRAIN CONTROL MODULE (BEHIND RIGHT RED WIRE SIDE OF DASH) TIMER LOGIC, RELAY MODULE (RIGHT SIDE OF FIREWALL) TRANSFER CASE MODE SELECTOR ILLUMINATION LAMP TRANSFER CASE SYNCHRONIZER (TOP OF TRANSFER CASE) VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT)

AUXILIARY BATTERY RELAY BLK WIRE BLK/WHT WIRE BRN WIRE DIESEL FRONT AXLE ACTUATOR FUSE 24 GASOLINE GRY WIRE GRY/BLK WIRE HARN) HOT IN PARK OR HEAD HOT IN RUN I/P FUSE BLOCK (LEFT SIDE OF DASH, ILLUM FUSE 14 INDICATOR LT BLU WIRE M/T A/T POWERTRAIN CONTROL MODULE (BEHIND RIGHT RED WIRE SIDE OF DASH) TIMER LOGIC, RELAY MODULE (RIGHT SIDE OF FIREWALL) TRANSFER CASE MODE SELECTOR ILLUMINATION LAMP TRANSFER CASE SYNCHRONIZER (TOP OF TRANSFER CASE) VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT)

AUXILIARY BATTERY RELAY BLK WIRE BLK/WHT WIRE BRN WIRE DIESEL FRONT AXLE ACTUATOR FUSE 24 GASOLINE GRY WIRE GRY/BLK WIRE HARN) HOT IN PARK OR HEAD HOT IN RUN I/P FUSE BLOCK (LEFT SIDE OF DASH, ILLUM FUSE 14 INDICATOR LT BLU WIRE M/T A/T POWERTRAIN CONTROL MODULE (BEHIND RIGHT RED WIRE SIDE OF DASH) TIMER LOGIC, RELAY MODULE (RIGHT SIDE OF FIREWALL) TRANSFER CASE MODE SELECTOR ILLUMINATION LAMP TRANSFER CASE SYNCHRONIZER (TOP OF TRANSFER CASE) VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT)

1-2 SHIFT SOLENOID 2-3 SHIFT SOLENOID 29 30 VSS LO (GROUND) VSS HI (SIGNAL) ANTI-LOCK BRAKES SYSTEM AUTOMATIC TRANSMISSION BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE CRUISE CONTROL DK BLU WIRE ECM 1 FUSE ECM-B FUSE ELECTRONIC BRAKE CONTROL MODULE ENGINE CONTROLS ENGINE COOLANT TEMPERATURE SENSOR (TOP RIGHT FRONT OF ENGINE) FLUID TEMP SENSOR FRONT WHEEL LOCK FUEL INJECTORS, IGNITION CONTROL MOUDULE, IGNITION COIL FUEL PUMP, OIL PRESS SWITCH/ SENDER, FUEL PUMP RELAY GRY WIRE GRY/BLK WIRE HI LO HOT AT ALL TIMES HOT IN HOT IN OFF, RUN OR START HOT IN RUN OR START HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DSAH) GAUGES FUSE 4 I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) INLINE GENDER ADAPTOR INSTRUMENT CLUSTER LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MALFUNCTION INDICATOR LAMP ORG/ WIRE PNK PNK WIRE PNK WIRE PPL PPL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) PPL/WHT WIRE PRESS CTRL SOLENOID RED WIRE RED/BLK WIRE REV, LO RUN WIRE TAN WIRE TCC PWM SOLENOID TCC/ABS/ CRUISE SWITCH THROTTLE POSITION SENSOR (MOUNTED TO SIDE OF THROTTLE BODY) TRANS FUSE 20 TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANSFER CASE CIRCUIT TRANSFER CASE, AXLE SWITCHES UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT SIDE OF YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOLENOID 2-3 SHIFT SOLENOID A/T ISS SENSOR VSS IN SENSOR GROUND SENSOR GROUND APP 1 SIGNAL IN ACCELERATOR PEDAL POSITION MODULE (PART OF ACCELERATOR PEDAL) APP 3 SIGNAL IN SENSOR GROUND A/T ISS SENS LO AUTOMATIC TRANSMISSION BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE DK BLU WIRE DK GRN WIRE ECM-B FUSE ELECTRONIC BRAKE CONTROL MODULE PPL ENGINE CONTROLS SYSTEM ENGINE SHUTOFF SOLENOID, FUEL SOLENOID EXTERIOR LIGHTS FUEL PUMP, OIL PRESS SWITCH/ SENDER, FUEL PUMP RELAY GAUGES FUSE 4 GRY WIRE GRY/BLK WIRE HI LO HOT AT ALL TIMES HOT IN HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) INLINE GENDER ADAPTOR INSTRUMENT CLUSTER LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MALFUNCTION INDICATOR LAMP ORG/ WIRE PNK PPL WIRE PNK WIRE POWERTRAIN CONTROL MODULE (RIGHT SIDE OF DASH NEAR BLOWER MOTOR) PPL PPL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) PPL PNK PNK WIRE PPL PRESS CTRL SOLENOID PPL/WHT WIRE RED WIRE RED/BLK WIRE RUN WIRE STOP/HAZ FUSE 1 TAN WIRE TAN/WHT WIRE TCC PWM SOLENOID TRANS FLUID TEMP SENSOR TRANS FUSE 20 TRANS RANGE PNK PNK REV, LO WIRE TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANSFER CASE CIRCUIT TRANSFER CASE CIRCUIT PNK WIRE TURN/ HAZARD SWITCH, CHIME MODULE VEHICLE SPEED SENSOR (LEFT SIDE OF VEHICLE SPEED SENSOR BUFFER (RIGHT SIDE OF DASH) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

1-2 SHIFT SOLENOID 2-3 SHIFT SOLENOID 29 30 VSS LO (GROUND) VSS HI (SIGNAL) ANTI-LOCK BRAKES SYSTEM AUTOMATIC TRANSMISSION BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRAKE FUSE 18 BRN WIRE BRN/WHT WIRE CRUISE CONTROL DK BLU WIRE ECM 1 FUSE ECM-B FUSE ELECTRONIC BRAKE CONTROL MODULE ENGINE CONTROLS ENGINE COOLANT TEMPERATURE SENSOR (TOP RIGHT FRONT OF ENGINE) FLUID TEMP SENSOR FRONT WHEEL LOCK FUEL INJECTORS, IGNITION CONTROL MOUDULE, IGNITION COIL FUEL PUMP, OIL PRESS SWITCH/ SENDER, FUEL PUMP RELAY GRY WIRE GRY/BLK WIRE HI LO HOT AT ALL TIMES HOT IN HOT IN OFF, RUN OR START HOT IN RUN OR START HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DSAH) GAUGES FUSE 4 I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) INLINE GENDER ADAPTOR INSTRUMENT CLUSTER LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MALFUNCTION INDICATOR LAMP ORG/ WIRE PNK PNK WIRE PNK WIRE PPL PPL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) PPL/WHT WIRE PRESS CTRL SOLENOID RED WIRE RED/BLK WIRE REV, LO RUN WIRE TAN WIRE TCC PWM SOLENOID TCC/ABS/ CRUISE SWITCH THROTTLE POSITION SENSOR (MOUNTED TO SIDE OF THROTTLE BODY) TRANS FUSE 20 TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANSFER CASE CIRCUIT TRANSFER CASE, AXLE SWITCHES UNDERHOOD FUSE/RELAY CENTER (LEFT REAR OF ENGINE COMPT) VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED SENSOR (LEFT SIDE OF YEL WIRE YEL/BLK WIRE