GMC Suburban K2500 (1985-1999) red Wiring diagrams

1 2 3 4 5 6 7 8 9 10 ILLUMINATION GROUND AIR TEMP DR SENSOR MODE SIGNAL BATTERY IGNITION GROUND DEFOGGER ELEMENT BLK WIRE BLOWER FUSE 3 BLOWER MOTOR (UNDER RIGHT SIDE OF DASH) BLOWER RESISTOR (ON BLOWER MOTOR HOUSING) BLOWER SWITCH BRN WIRE DK BLU WIRE DK GRN WIRE FRONT MODE DOOR MOTOR (ON FRONT A/C-HEATER HOUSING) FRONT TEMPERATURE DOOR MOTOR (ON FRONT A/C-HEATER HOUSING) FUSE BLOCK GRY WIRE HIGH BLOWER RELAY (ON TOP OF FRONT A/C- HEATER BLOWER HOUSING) HOT AT ALL TIMES HOT IN RUN HTR A/C FUSE 12 HVAC CONTROL MODULE LT BLU WIRE OFF LO ORG/ WIRE PPL REAR DEFOGGER SYSTEM RECIRC CTRL IGNITION RECIRCULATION DOOR MOTOR (ON FRONT A/C-HEATER HOUSING) RED WIRE TAN WIRE UNDERHOOD FUSE/RELAY CENTER WHT WIRE YEL WIRE

1 2 3 4 5 6 7 8 9 10 ILLUMINATION GROUND 1995 VFTC AIR TEMP DR SENSOR MODE SIGNAL AUXILIARY BLOWER MOTOR AUXILIARY BLOWER MOTOR RELAY, HIGH (ON AUXILIARY A/C PLENUM) AUXILIARY BLOWER MOTOR RELAY, LOW (ON AUXILIARY A/C PLENUM) AUXILIARY BLOWER MOTOR RELAY, MEDIUM (ON AUXILIARY A/C PLENUM) AUXILIARY BLOWER MOTOR RESISTOR (ON AUXILIARY A/C PLENUM) AUXILIARY HEATER CONTROL MODULE (REAR) (BEHIND LEFT SIDE OF DASH) BATTERY IGNITION GROUND DEFOGGER ELEMENT BLK WIRE BLOWER FUSE 3 BLOWER MOTOR (UNDER RIGHT SIDE OF DASH) BLOWER RESISTOR (ON BLOWER MOTOR HOUSING) BLOWER SWITCH BRN WIRE CONVENIENCE CENTER DK BLU WIRE DK GRN WIRE GRY WIRE HIGH BLOWER RELAY (ON TOP OF FRONT A/C- HEATER BLOWER HOUSING) HOT AT ALL TIMES HOT IN RUN HTR A/C FUSE 12 HVAC CONTROL MODULE I/P FUSE BLOCK LT BLU WIRE MEGA FUSE BLOCK OFF LO OFF LOW MED HIGH ORG/ WIRE PPL REAR DEFOGGER SYSTEM REAR OFF LOW MED HIGH RECIRC CTRL IGNITION RECIRCULATION DOOR MOTOR (ON FRONT A/C-HEATER HOUSING) RED WIRE RR HVAC FUSE 5 TAN WIRE WHT WIRE YEL WIRE

1 2 3 4 5 6 7 8 9 10 ILLUMINATION GROUND A/C DISABLE RECIRC DOOR SIGNAL IGNITION A/C COMPRESSOR CLUTCH A/C COMPRESSOR CLUTCH RELAY (IN UNDERHOOD FUSE/RELAY CENTER) A/C COMPRESSOR CYCLING SWITCH (IN LOW PRESSURE LINE, ON ACCUMULATOR) A/C CTRL A/C HIGH PRESSURE CUTOUT SWITCH (ON A/C COMPRESSOR) A/C LOW PRESSURE CUTOUT SWITCH (ON A/C COMPRESSOR) A/C REQ AIR TEMP DR SENSOR MODE SIGNAL A/C SWITCH AUX FAN FUSE AUXILIARY COOLING FAN MOTOR AUXILIARY COOLING FAN RELAY (EXC 4.3L) (IN UNDERHOOD FUSE/RELAY CENTER) BATTERY IGNITION GROUND DEFOGGER ELEMENT BLK WIRE BLK/WHT WIRE BLOWER MOTOR (UNDER RIGHT SIDE OF DASH) BLOWER RESISTOR (ON BLOWER MOTOR HOUSING) BLOWER SWITCH BRN WIRE DIODE DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE FRONT RECIRCULATION DOOR MOTOR (ON FRONT A/C-HEATER HOUSING) FUSE BLOCK GRY WIRE HIGH BLOWER RELAY (ON TOP OF FRONT A/C-HEATER HOUSING) HOT AT ALL TIMES HOT AT ALL TIMES UNDERHOOD BLOWER FUSE 3 FUSE BLOCK HOT IN RUN HOT IN RUN OR START HTR A/C FUSE 12 HVAC CONTROL MODULE IGN E FUSE A/C COMP FUSE LT BLU WIRE LT GRN WIRE OFF LO ORG/ WIRE PNK WIRE PPL REAR DEFOGGER SYSTEM RED WIRE SW SIG SW SIG RELAY CTRL TAN WIRE UNDERHOOD FUSE BLOCK VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) WHT WIRE YEL WIRE

1 2 3 4 5 6 7 8 9 10 ILLUMINATION GROUND A/C DISABLE RECIRC CTRL IGNITION 1995 VFTC A/C COMPRESSOR CLUTCH A/C COMPRESSOR CLUTCH DIODE A/C COMPRESSOR CLUTCH RELAY (IN UNDERHOOD FUSE BOX) A/C COMPRESSOR CYCLING SWITCH (ON TOP OF ACCUMULATOR) A/C COMPRESSOR HIGH PRESSURE CUTOUT SWITCH (REAR OF THE A/C COMPRESSOR) A/C COMPRESSOR LOW PRESSURE CUTOUT SWITCH (ON TOP OF A/C COMPRESSOR) A/C FUSE A/C REQUEST AIR TEMP DR SENSOR MODE SIGNAL A/C REQUEST AUX FAN FUSE AUXILIARY COOLING FAN MOTOR AUXILIARY COOLING FAN RELAY (IN UNDERHOOD FUSE/RELAY CENTER) BATTERY IGNITION GROUND DEFOGGER ELEMENT BLK WIRE BLK/WHT WIRE BLOWER FUSE 3 BLOWER MOTOR (UNDER RIGHT SIDE OF DASH) BLOWER RESISTOR (ON BLOWER MOTOR HOUSING) BLOWER SWITCH OFF LO BRN WIRE DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE GRY WIRE HIGH BLOWER RELAY (ON TOP OF FRONT A/C- HEATER BLOWER HOUSING) HOT AT ALL TIMES HOT IN RUN HOT IN RUN I/P IGN E FUSE FUSE BLOCK HTR A/C FUSE 12 HVAC CONTROL MODULE LT BLU WIRE LT GRN WIRE ORG/ WIRE PNK WIRE PPL REAR DEFOGGER SYSTEM RECIRCULATION DOOR MOTOR (ON FRONT A/C-HEATER HOUSING) RED WIRE RELAY CONTROL SWITCH SIGNAL TAN WIRE UNDERHOOD FUSE BLOCK VEHICLE CONTROL MODULE (ENGINE COMPARTMENT NEAR EBCM) WHT WIRE YEL WIRE

2-HI IND 4-HI IND 4-LO IND AUTO AUTOMATIC TRANSFER CASE AUTOMATIC TRANSFER CASE CONTROL MODULE (STEERING COLUMN BRACKET) 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 DECODER LOGIC DK BLU/WHT WIRE DK GRN WIRE 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 GASOLINE 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) WHT WIRE YEL WIRE YEL/BLK WIRE

2-HI IND 4-HI IND 4-LO IND AUTO AUTOMATIC TRANSFER CASE AUTOMATIC TRANSFER CASE CONTROL MODULE (STEERING COLUMN BRACKET) 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 DECODER LOGIC DK BLU/WHT WIRE DK GRN WIRE 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 GASOLINE 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) WHT WIRE YEL WIRE YEL/BLK WIRE

2-HI IND 4-HI IND 4-LO IND AUTO AUTOMATIC TRANSFER CASE AUTOMATIC TRANSFER CASE CONTROL MODULE (STEERING COLUMN BRACKET) 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 DECODER LOGIC DK BLU/WHT WIRE DK GRN WIRE 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 GASOLINE 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) WHT WIRE YEL WIRE YEL/BLK WIRE

A/T ANTI-LOCK BRAKES SYSTEM BLK WIRE BLK/WHT WIRE BLU WIRE BRN WIRE DIESEL FROM ABS CONTROL MODULE) FRONT AXLE ACTUATOR FUSE 24 GASOLINE GRY WIRE GRY/BLK WIRE HEAVY-DUTY TRANSFER CASE HOT IN PARK OR HEAD HOT IN RUN I/P FUSE BLOCK (LEFT SIDE OF DASH, ILLUM FUSE 14 INDICATOR INTERIOR LIGHTS SYSTEM (SUBURBAN W/ A/C ONLY) LT BLU WIRE LT N/A M/T POWERTRAIN CONTROL MODULE (DIESEL) RED WIRE SEAT BELT SWITCH TRANSFER CASE MODE SELECTOR ILLUMINATION LAMP TRANSFER CASE RELAY (RIGHT SIDE OF FIREWALL) TRANSFER CASE SWITCH (TOP LEFT OF TRANSFER CASE) TRANSFER CASE SYNCHRONIZER (TOP OF TRANSFER CASE) VEHICLE CONTROL MODULE (GASOLINE) (LEFT SIDE OF ENGINE COMPT) WHT WIRE

A/T ANTI-LOCK BRAKES SYSTEM BLK WIRE BLK/WHT WIRE BLU WIRE BRN WIRE DIESEL FROM ABS CONTROL MODULE) FRONT AXLE ACTUATOR FUSE 24 GASOLINE GRY WIRE GRY/BLK WIRE HEAVY-DUTY TRANSFER CASE HOT IN PARK OR HEAD HOT IN RUN I/P FUSE BLOCK (LEFT SIDE OF DASH, ILLUM FUSE 14 INDICATOR INTERIOR LIGHTS SYSTEM (SUBURBAN W/ A/C ONLY) LT BLU WIRE LT N/A M/T POWERTRAIN CONTROL MODULE (DIESEL) RED WIRE SEAT BELT SWITCH TRANSFER CASE MODE SELECTOR ILLUMINATION LAMP TRANSFER CASE RELAY (RIGHT SIDE OF FIREWALL) TRANSFER CASE SWITCH (TOP LEFT OF TRANSFER CASE) TRANSFER CASE SYNCHRONIZER (TOP OF TRANSFER CASE) VEHICLE CONTROL MODULE (GASOLINE) (LEFT SIDE OF ENGINE COMPT) WHT WIRE

A/T ANTI-LOCK BRAKES SYSTEM BLK WIRE BLK/WHT WIRE BLU WIRE BRN WIRE DIESEL FROM ABS CONTROL MODULE) FRONT AXLE ACTUATOR FUSE 24 GASOLINE GRY WIRE GRY/BLK WIRE HEAVY-DUTY TRANSFER CASE HOT IN PARK OR HEAD HOT IN RUN I/P FUSE BLOCK (LEFT SIDE OF DASH, ILLUM FUSE 14 INDICATOR INTERIOR LIGHTS SYSTEM (SUBURBAN W/ A/C ONLY) LT BLU WIRE LT N/A M/T POWERTRAIN CONTROL MODULE (DIESEL) RED WIRE SEAT BELT SWITCH TRANSFER CASE MODE SELECTOR ILLUMINATION LAMP TRANSFER CASE RELAY (RIGHT SIDE OF FIREWALL) TRANSFER CASE SWITCH (TOP LEFT OF TRANSFER CASE) TRANSFER CASE SYNCHRONIZER (TOP OF TRANSFER CASE) VEHICLE CONTROL MODULE (GASOLINE) (LEFT SIDE OF ENGINE COMPT) WHT WIRE