GMC Suburban C2500 (1985-1999) blk Wiring diagrams

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

1 2 3 4 5 6 7 8 9 10 ILLUMINATION GROUND A/C DISABLE AUX FAN CTRL 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 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 FUSE 3 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 MODE DOOR MOTOR (ON FRONT A/C-HEATER HOUSING) FUSE BLOCK GRY WIRE GRY/BLK WIRE HIGH BLOWER RELAY (ON TOP OF FRONT A/C-HEATER HOUSING) HOT AT ALL TIMES HOT AT ALL TIMES UNDERHOOD FUSE-RELAY CENTER 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-RELAY CENTER VALVE CTRL AIR TEMP DR SENSOR MODE SIGNAL A/C SWITCH VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) WATER VALVE (SUBURBAN, UTILITY, CREW CAB ONLY) (RIGHT CENTER OF INTAKE AREA) WHT WIRE YEL WIRE

1995 VFTC 77 OR 1923 8 150 INTERIOR LIGHTS SYSTEM AUXILIARY BLOWER MOTOR (BEHIND RIGHT REAR WHEELWELL) AUXILIARY BLOWER RESISTOR (TOP OF AUX HVAC PLENUM) AUXILIARY HIGH BLOWER RELAY (ON AUXILIARY A/C-HEATER HOUSING) AUXILIARY HVAC CONTROL LOGIC MODULE (OVERHEAD CONSOLE) AUXILIARY HVAC CONTROL MODULE (FRONT) (OVERHEAD CONSOLE) AUXILIARY HVAC CONTROL MODULE (REAR) (OVERHEAD CONSOLE) AUXILIARY LOW BLOWER RELAY (ON AUXILIARY A/C-HEATER HOUSING) AUXILIARY MEDIUM BLOWER RELAY (ON AUXILIARY A/C-HEATER HOUSING) AUXILIARY MODE DOOR ACTUATOR AUXILIARY TEMP DOOR ACTUATOR BATTERY BLK WIRE BRN WIRE CONTROL INPUT CONVENIENCE CENTER (UNDER LEFT SIDE OF I/P) DK BLU OR ORG WIRE DK BLU WIRE FUSE BLOCK GROUND GROUND IGNITION GRY WIRE HOT AT ALL TIMES BLOWER FUSE 3 HOT IN RUN LT BLU WIRE ORG/ WIRE REAR CTRL A/C FRT CTRL A/C RED WIRE RR HVAC UNDERHOOD FUSE/RELAY CENTER W/ HTR W/O HTR WHT WIRE YEL WIRE

1995 VFTC 77 OR 1923 8 150 INTERIOR LIGHTS SYSTEM AUXILIARY BLOWER MOTOR (BEHIND RIGHT REAR WHEELWELL) AUXILIARY BLOWER RESISTOR (TOP OF AUX HVAC PLENUM) AUXILIARY HIGH BLOWER RELAY (ON AUXILIARY A/C-HEATER HOUSING) AUXILIARY HVAC CONTROL LOGIC MODULE (OVERHEAD CONSOLE) AUXILIARY HVAC CONTROL MODULE (FRONT) (OVERHEAD CONSOLE) AUXILIARY HVAC CONTROL MODULE (REAR) (OVERHEAD CONSOLE) AUXILIARY LOW BLOWER RELAY (ON AUXILIARY A/C-HEATER HOUSING) AUXILIARY MEDIUM BLOWER RELAY (ON AUXILIARY A/C-HEATER HOUSING) AUXILIARY MODE DOOR ACTUATOR AUXILIARY TEMP DOOR ACTUATOR BATTERY BLK WIRE BRN WIRE CONTROL INPUT CONVENIENCE CENTER (UNDER LEFT SIDE OF I/P) DK BLU OR ORG WIRE DK BLU WIRE FUSE BLOCK GROUND GROUND IGNITION GRY WIRE HOT AT ALL TIMES BLOWER FUSE 3 HOT IN RUN LT BLU WIRE ORG/ WIRE REAR CTRL A/C FRT CTRL A/C RED WIRE RR HVAC UNDERHOOD FUSE/RELAY CENTER W/ HTR W/O HTR WHT WIRE YEL WIRE

1995 VFTC 77 OR 1923 8 150 INTERIOR LIGHTS SYSTEM AUXILIARY BLOWER MOTOR (BEHIND RIGHT REAR WHEELWELL) AUXILIARY BLOWER RESISTOR (TOP OF AUX HVAC PLENUM) AUXILIARY HIGH BLOWER RELAY (ON AUXILIARY A/C-HEATER HOUSING) AUXILIARY HVAC CONTROL LOGIC MODULE (OVERHEAD CONSOLE) AUXILIARY HVAC CONTROL MODULE (FRONT) (OVERHEAD CONSOLE) AUXILIARY HVAC CONTROL MODULE (REAR) (OVERHEAD CONSOLE) AUXILIARY LOW BLOWER RELAY (ON AUXILIARY A/C-HEATER HOUSING) AUXILIARY MEDIUM BLOWER RELAY (ON AUXILIARY A/C-HEATER HOUSING) AUXILIARY MODE DOOR ACTUATOR AUXILIARY TEMP DOOR ACTUATOR BATTERY BLK WIRE BRN WIRE CONTROL INPUT CONVENIENCE CENTER (UNDER LEFT SIDE OF I/P) DK BLU OR ORG WIRE DK BLU WIRE FUSE BLOCK GROUND GROUND IGNITION GRY WIRE HOT AT ALL TIMES BLOWER FUSE 3 HOT IN RUN LT BLU WIRE ORG/ WIRE REAR CTRL A/C FRT CTRL A/C RED WIRE RR HVAC UNDERHOOD FUSE/RELAY CENTER W/ HTR W/O HTR WHT WIRE YEL WIRE

1995 VFTC AUXILIARY BLOWER MOTOR (BEHIND RIGHT REAR WHEELWELL) AUXILIARY BLOWER RESISTOR (TOP OF AUXILIARY HVAC PLENUM) AUXILIARY HEATER CONTROL MODULE BLK WIRE BLOWER FUSE BRN WIRE CONVENIENCE CENTER (UNDER LEFT SIDE OF I/P) DK BLU WIRE FUSE BLOCK GRY WIRE HOT AT ALL TIMES HOT IN RUN HOT W/HEADLAMP SWITCH IN PARK OR HEAD ILLUM FUSE 14 LT BLU WIRE OFF LOW MED HI REAR HIGH BLOWER RELAY (ON AUXILIARY HEATER HOUSING) REAR LOW BLOWER RELAY (ON AUXILIARY HEATER HOUSING) REAR MEDIUM BLOWER RELAY (ON AUXILIARY HEATER HOUSING) RED WIRE RR HVAC FUSE 5 UNDERHOOD FUSE/RELAY CENTER WHT WIRE YEL WIRE

1995 VFTC AUXILIARY BLOWER MOTOR (BEHIND RIGHT REAR WHEELWELL) AUXILIARY BLOWER RESISTOR (TOP OF AUXILIARY HVAC PLENUM) AUXILIARY HEATER CONTROL MODULE BLK WIRE BLOWER FUSE BRN WIRE CONVENIENCE CENTER (UNDER LEFT SIDE OF I/P) DK BLU WIRE FUSE BLOCK GRY WIRE HOT AT ALL TIMES HOT IN RUN HOT W/HEADLAMP SWITCH IN PARK OR HEAD ILLUM FUSE 14 LT BLU WIRE OFF LOW MED HI REAR HIGH BLOWER RELAY (ON AUXILIARY HEATER HOUSING) REAR LOW BLOWER RELAY (ON AUXILIARY HEATER HOUSING) REAR MEDIUM BLOWER RELAY (ON AUXILIARY HEATER HOUSING) RED WIRE RR HVAC FUSE 5 UNDERHOOD FUSE/RELAY CENTER WHT WIRE YEL WIRE

1995 VFTC AUXILIARY BLOWER MOTOR (BEHIND RIGHT REAR WHEELWELL) AUXILIARY BLOWER RESISTOR (TOP OF AUXILIARY HVAC PLENUM) AUXILIARY HEATER CONTROL MODULE BLK WIRE BLOWER FUSE BRN WIRE CONVENIENCE CENTER (UNDER LEFT SIDE OF I/P) DK BLU WIRE FUSE BLOCK GRY WIRE HOT AT ALL TIMES HOT IN RUN HOT W/HEADLAMP SWITCH IN PARK OR HEAD ILLUM FUSE 14 LT BLU WIRE OFF LOW MED HI REAR HIGH BLOWER RELAY (ON AUXILIARY HEATER HOUSING) REAR LOW BLOWER RELAY (ON AUXILIARY HEATER HOUSING) REAR MEDIUM BLOWER RELAY (ON AUXILIARY HEATER HOUSING) RED WIRE RR HVAC FUSE 5 UNDERHOOD FUSE/RELAY CENTER WHT WIRE YEL WIRE

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 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 RED WIRE TAN WIRE UNDERHOOD FUSE-RELAY CENTER WHT WIRE YEL WIRE

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 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 RED WIRE TAN WIRE UNDERHOOD FUSE-RELAY CENTER WHT WIRE YEL WIRE