GMC Pickup K2500 (1985-2000) org/ Wiring diagrams

A/C COMP FUSE A/C COMPRESSOR CLUTCH A/C COMPRESSOR CLUTCH RELAY (IN UNDERHOOD FUSE-RELAY CENTER) A/C COMPRESSOR CYCLING SWITCH A/C CONTROL A/C DISABLE A/C HIGH PRESSURE CUTOUT SWITCH (ON A/C COMPRESSOR) A/C LOW PRESSURE CUTOUT SWITCH A/C REQ A/C SWITCH BLK WIRE BLK/ WHT WIRE BLOWER SWITCH BRN WIRE DIODE DK BLU WIRE DK GRN WIRE DK GRN/WHT WIRE FUSE BLOCK HOT IN RUN HVAC CONTROL MODULE HTR A/C FUSE 12 HOT IN RUN OR START IGNITION LO OFF LT GRN WIRE ORG/ WIRE PNK WIRE SW SIG UNDERHOOD FUSE-RELAY CENTER IGN E FUSE VEHICLE CONTROL MODULE (LEFT SIDE OF ENGINE COMPT) WHT WIRE

1-2 SHIFT SOL 1-2 SHIFT SOLENOID 2-3 SHIFT SOL 2-3 SHIFT SOLENOID A/T ISS HI IN A/T ISS LO IN AUTOMATIC TRANSMISSION BATTERY IN BLK WIRE BLK/WHT WIRE BLU/WHT WIRE BRAKE FUSE 18 BRAKE SWITCH ASSEMBLY (ON BRAKE PEDAL BRACKET) BRAKE SWITCH INPUT BRN WIRE BRN/WHT WIRE DATA CLASS II DK BLU WIRE ECM 1 FUSE ECM-B FUSE ECT SENS INPUT ELECTRONIC BRAKE CONTROL MODULE ENG 1 FUSE FRONT WHEEL LOCK FUEL INJECTORS, IGNITION CONTROL MOUDULE, IGNITION COIL FUEL PUMP, OIL PRESS SWITCH/ SENDER, FUEL PUMP RELAY GAUGES FUSE 4 GRY WIRE GRY/BLK WIRE HEADLAMP, PANEL DIMMER SWITCH PNK WIRE HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK IGNITION IN INSTRUMENT CLUSTER LEFT REAR SIDE LT BLU WIRE LT BLU/WHT WIRE LT GRN WIRE LT GRN/BLK WIRE MAF SENSOR, HEATED OXYGEN SENSORS MALFUNCTION INDICATOR LAMP MIL CONTROL ORG/ WIRE PCM GROUND PCS SOL HI OUT PCS SOL LO OUT PNK WIRE PPL PPL DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) PPL/WHT WIRE PRESS CTRL HI SOLENOID LO RANGE SIGNAL "A" RANGE SIGNAL "B" RANGE SIGNAL "C" RED WIRE RED/BLK WIRE SENSOR GROUND SENSOR RETURN TAN WIRE TCC PWM SOL TCC PWM SOLENOID THROTTLE POSITION SENSOR (MOUNTED TO SIDE OF THROTTLE BODY) TP SENS INPUT TRANS FLUID TEMP SENSOR TRANS FUSE 20 TRANS RANGE PRESSURE SWITCH ASSEMBLY TRANS RANGE SWITCHES TRANS TEMP SIG IN TRANSFER CASE, AXLE SWITCHES UNDERHOOD FUSE/RELAY CENTER VEHICLE CONTROL MODULE (VCM) (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED SENSOR VEHICLE SPEED SENSOR ADAPTOR VSS HI VSS LO YEL WIRE YEL/BLK WIRE

BLK WIRE CARGO LAMP CTRL CTSY FUSE 3 DOME DEFEAT DOME DEFEAT IGN SW DOOR JAMB FRONT DOME AND READING LAMP GRY WIRE HEADLAMP AND PANEL DIMMER SWITCH DOME LAMP DEFEAT COURTESY LAMPS HOT AT ALL TIMES HOT IN RUN, BULB TEST OR START I/P COMPARTMENT BOX LAMP I/P FUSE BLOCK I/P FUSE BLOCK GAGES FUSE 4 IGN SW INTERIOR LAMP CONTROL MODULE (UNDER CENTER OF DASH) LAMP OUT LEFT I/P COURTESY LAMP LEFT ILLUMINATED VANITY MIRROR MIRRORS SYSTEM NCA WIRE ORG/ WIRE PNK WIRE PPL (NOT USED) PPL PPL REMOTE CONTROL DOOR LOCK RECEIVER (BEHIND CENTER OF DASH) RIGHT FRONT DOOR JAMB SWITCH LEFT FRONT DOOR JAMB SWITCH RIGHT I/P COURTESY LAMP RIGHT ILLUMINATED VANITY MIRROR UNDERHOOD FUSE-RELAY CENTER HORN FUSE UNDERHOOD LAMP UNDERHOOD REEL LAMP W/ RKE W/O RKE WHT WIRE

BLK WIRE CONVENIENCE CENTER (UNDER LEFT SIDE OF DASH) GRY WIRE HOT AT ALL TIMES I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) LEFT FRONT DOOR LOCK MOTOR LEFT FRONT DOOR LOCK SWITCH LOCK LT BLU WIRE ORG/ WIRE PWR-ACCY CIRCUIT BREAKER RIGHT FRONT DOOR LOCK MOTOR RIGHT FRONT DOOR LOCK SWITCH SOLID STATE TAN WIRE UNLOCK WHT WIRE

1134 1134 39 10 10 PARK BRAKE SIG IND BULB CHK IGNITION LAMP FEED PNK WIRE 33 33 BRAKE IND CTRL BRAKE WARN IN 592 592 150 DRL RELAY CTRL BLK WIRE BLK/WHT WIRE BRN WIRE BULB TEST CONVENIENCE CENTER (UNDER LEFT SIDE OF DASH) DAYTIME RUNNING LAMP MODULE (BEHIND LEFT SIDE OF DASH) DAYTIME RUNNING LAMPS RELAY DIODE 203 DRL INDICATOR DRL-FOG FUSE 15 FOG LAMP RELAY FOG LAMP SWITCH GAUGES FUSE 4 GRN WIRE GROUND GRY WIRE HEAD OFF PARK HEAD- LAMP DIMMER SWITCH HEADLAMP, PANEL DIMMER SWITCH HIGH BEAM INDICATOR HOT AT ALL TIMES HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK (LEFT SIDE OF DASH, IGNITION SWITCH ILLUM LAMP INSTRUMENT CLUSTER INSTRUMENT CLUSTER SYSTEM (BRAKE WARNING INDICATOR) LEFT FOG LAMP LEFT HEAD- LAMP RIGHT HEAD- LAMP LIGHTING FUSE 8 LOCK OFF LT BLU WIRE LT GRN WIRE LT GRN/BLK WIRE NCA WIRE OFF ON INDICATOR ORG/ WIRE PARK BRAKE WARNING SWITCH PK LPS FUSE 9 PNK WIRE PPL RED WIRE RIGHT FOG LAMP RUN WIRE TAN WIRE TAN/WHT WIRE UNDERHOOD FUSE BLOCK (LEFT REAR OF ENGINE COMPT) W/ FOG LAMPS WHT WIRE YEL WIRE

BATT B BELT SWITCH BREAKOUT) BLK WIRE BLK/WHT WIRE CIG LTR FUSE 13 CONVENIENCE CENTER (LEFT SIDE OF DASH) DATA LINK CONNECTOR (UNDER LEFT SIDE OF DASH) DOOR LOCK RELAY (UNDER CENTER OF DASH, NEAR REMOTE CONTROL DOOR LOCK RECEIVER) DRIVER DR UNLK UNLOCK OUT HORN SIGNAL GAUGES FUSE 4 GROUND GRY WIRE HORNS SYSTEM HOT AT ALL TIMES HOT IN RUN, BULB TEST OR START I/P FUSE BLOCK (LEFT SIDE OF DASH, INTERIOR LAMPS SYSTEM LEFT DOOR LOCK SWITCH LEFT FRONT DOOR LOCK ACTUATOR LOCK LOCK OUT DOME LAMPS LT BLU WIRE ORG/ WIRE PASS DRS UNLK PNK IGNITION DOME LMP OFF PROGRAM SIG WIRE PNK WIRE PWR ACCY C.B. REMOTE CONTROL DOOR LOCK RECEIVER (UNDER CENTER OF DASH PANEL) RIGHT DOOR LOCK SWITCH RIGHT FRONT DOOR LOCK ACTUATOR SEAT BELT SWITCH BREAKOUT) TAN WIRE UNLOCK W/O POWER WINDOWS W/ POWER WINDOWS WHT WIRE

6-WAY POWER SEAT CIRCUIT BLK WIRE CONVENIENCE CENTER (UNDER LEFT SIDE OF DASH) DK BLU WIRE HOT AT ALL TIMES I/P FUSE BLOCK LEFT POWER LUMBAR SUPPORT MOTOR LEFT POWER SEAT LUMBAR SWITCH NCA WIRE ORG/ WIRE POWER SEAT ADJUSTER SWITCH PWR-ACCY CIRCUIT BREAKER RIGHT POWER LUMBAR SUPPORT MOTOR RIGHT POWER SEAT LUMBAR SWITCH

6-WAY POWER SEAT CIRCUIT BLK WIRE CIG LTR FUSE 13 CONVENIENCE CENTER (UNDER LEFT SIDE OF I/P) HOT AT ALL TIMES I/P FUSE BLOCK (LOWER LEFT SIDE OF I/P) LEFT POWER LUMBAR SUPPORT SWITCH ORG/ WIRE PNK LEFT POWER LUMBAR SUPPORT MOTOR WIRE PNK WIRE RIGHT POWER LUMBAR SUPPORT MOTOR RIGHT POWER LUMBAR SUPPORT SWITCH SUBURBAN, UTILITY ONLY

2-HI IND 2-HI SW 4 LO INDIC CTRL 4 LO SW 4 LOW SELECT SW IN 2 HI SELECT SW IN 4 HI SELECT SW IN BATTERY IN 4-HI IND 4-HI SW 4-LO IND ANTI-LOCK BRAKES SYSTEM BLK WIRE BLK/WHT WIRE BRN WIRE BRN/WHT WIRE CHANNEL A CHANNEL B CHANNEL C CHANNEL P DATA LINK CONNECTOR (PARTIAL) (UNDER LEFT SIDE OF DASH) DIESEL DK BLU/WHT WIRE DK GRN/WHT WIRE ENGINE CONTROLS, CRUISE CONTROL, SOUND SYSTEMS, INSTRUMENT CLUSTER EXTERIOR LIGHTS FRONT AXLE ACTUATOR FRONT AXLE SWITCH FUSE 24 GASOLINE GAUGES FUSE 4 GROUND GROUND GROUND BATTERY IN BATTERY IN PNP SW-P/N IN GRY WIRE GRY/BLK WIRE HEADLAMP, PANEL DIMMER SWITCH HOT AT ALL TIMES HOT IN RUN HOT IN RUN OR START I/P FUSE BLOCK (UNDER LEFT SIDE OF DASH) IGNITION IN ENCODER GROUND GROUND 2 HI INDIC CTRL 4 HI INDIC CTRL ILLUMINATION LAMP LOW SIG LT GRN WIRE LT GRN/BLK WIRE ORG/ WIRE OUTPUT VSS PARK/NEUTRAL POSITION SWITCH (ON LEFT SIDE, CENTER OF TRANSMISSION) PNK WIRE POWERTRAIN CONTROL MODULE (DIESEL) (BEHIND RIGHT SIDE OF DASH) PPL/WHT WIRE RED WIRE RED/WHT WIRE SIG AXLE SPARE POWER SOURCE AUXILIARY BATTERY RELAY TAN/BLK WIRE TCASE FUSE 2 TCC/STOP LAMP SWITCH (TOP OF BRAKE PEDAL) TRANSFER CASE CONTROL MODULE (STEERING COLUMN BRACKET) TRANSFER CASE ENCODER (RIGHT SIDE CENTER OF TRANSFER CASE) TRANSFER CASE ENCODER MOTOR (RIGHT SIDE OF TRANSFER CASE) TRANSFER CASE SELECT SWITCH TRANSFER CASE SWITCH (TOP LEFT OF TRANSFER CASE) TURN B/U FUSE 16 VEHICLE CONTROL MODULE (GASOLINE) (LEFT SIDE OF ENGINE COMPT) VEHICLE SPEED SENSOR BUFFER (DIESEL) (RIGHT SIDE OF DASH) YEL WIRE YEL/BLK WIRE

A/C REQUEST SIGNAL A/T 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 BRACKET) CPP SW INPUT FOUR WHL DR SIG LO CRUISE CTRL SIG ENG 23 24 A/T 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 BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE EGR VLV FEED 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 IGNITION CONTROL MODULE (ON REAR OF INTAKE MANIFOLD) IGNITION FEED IGN TIMING SIG. IGN COIL OUT IGNITION PRESSURE SWITCH INPUT PRESSURE SWITCH INPUT LT BLU/BLK WIRE LT BLU/WHT WIRE LT VSS SERIAL INPUT DATA SIG MANUAL OR AUTOMATIC 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 SPEED SENSOR SPEED STOPLAMP/ VCM SENSOR CLUTCH SIG INPUT SWITCH INPUT STOPLAMP SWITCH (TOP OF BRAKE PEDAL) SWITCH SIGNAL TRANSFER CASE CONTROL MODULE (UNDER DASH ON STEERING COLUMN SUPPORT BRACKET) 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