GMC Cab & Chassis Sierra 3500 HD (2008-2012) Automatic a/c circuit

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 AIR TMP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 B(+) A/C ON AIR TEMP RF SUNLD AMB AIR TMP GMLAN L AMBIENT AIR TEMPERATURE SENSOR (ON LEFT SIDE OF RADIATOR SUPPORT) AMBIENT LIGHT/SUNLOAD SENSOR ASSEMBLY (TOP CENTER OF DASH) AUTO BATT POS VOLT BLK WIRE BLK/WHT WIRE BREAKOUT) BRN WIRE COLNT LVL GROUND LOW REF COMPUTER DATA LINES SYSTEM DK BLU WIRE DK GRN WIRE ENGINE COOLANT LEVEL SWITCH (6.6L) (ON BOTTOM OF SURGE TANK) EVAPORATOR TEMPERATURE SENSOR (ON HVAC ASSEMBLY) FAN DN FAN UP FRESH AIR FRNT DFG FRT DEF A/C IND FSH AIR GROUND GROUND DISTRIBUTION SYSTEM GROUND IGN 3 REAR DEFOG GRY WIRE GRY/BLK WIRE HVAC CONTROL MODULE INSTRUMENT PANEL CLUSTER (IPC) DRIVER INFORMATION CENTER (DIC) DISPLAY LEFT I/P JUNCTION BLOCK (LOWER LEFT SIDE OF DASH) LEFT SUNLOAD SENSOR LEFT TEMP CONTROL LF SUNLD L AIR TMP R AIR TMP LOGIC LOW REF LT BLU WIRE LT BLU/BLK WIRE LT GRN WIRE LT GRN/BLK WIRE MODE DN MODE UP MTR SPD CTRL OFF ORG/ WIRE POWER DISTRIBUTION SYSTEM DEFOGGER SYSTEM PPL PPL/WHT WIRE R AIR TMP AIR TMP R AIR TMP TEMP SENS MODE CTRL L AIR TMP RECIR CTRL R AIR TMP REAR DFG RECIR RECIRC RED WIRE RED/WHT WIRE RER DEF RIGHT I/P JUNCTION BLOCK (IN RIGHT END OF DASH) RIGHT SUNLOAD SENSOR RIGHT TEMP CONTROL SERIAL DATA TAN WIRE UPPER LEFT AIR TEMPERATURE SENSOR (UNDER UPPER LEFT SIDE OF DASH) UPPER RIGHT AIR TEMPERATURE SENSOR (UNDER UPPER RIGHT SIDE OF DASH) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

19 14 69 71 RLY SPD SIG 22 21 4 58 40 24 30 46 LOW REF ECT SENS SIG 6.0L 6.6L 4.8L, 5.3L,, 6.2L 4.3L A/C CMPRSR FUSE 17 (EXCEPT 6.6L) FUSE 16 (6.6L) A/C CMPRSR RELAY BLK WIRE BRN WIRE BRN/WHT WIRE COMPUTER DATA LINES DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE DK GRN/WHT WIRE ENGINE COOLING FAN (6.6L) (FRONT CENTER OF ENGINE COMPT) EXCEPT 6.6L 6.6L FROM PWR/TRN RELAY (DIAGRAM 3 OF 3) GRY WIRE GRY/BLK WIRE HOT AT ALL TIMES HVAC BATT FUSE 39 HVAC BLWR FUSE 70 HVAC IGN FUSE 55 (EXCEPT 6.6L) FUSE 52 (6.6L) LT BLU WIRE LT BLU/BLK WIRE LT GRN WIRE ORG/BLK WIRE PNK WIRE PPL PPL/WHT WIRE RED WIRE RED/BLK WIRE RED/WHT WIRE RIGHT I/P JUNCTION BLOCK (IN RIGHT END OF DASH) RLY CTRL RUN/ CRNK RELAY SENS SIG PWRTRN RLY CTRL FAN RLY CTRL FAN RLY CTRL SPD SIG LOW REF SYSTEM 459 5514 TAN WIRE TAN/BLK WIRE UNDER- HOOD FUSE BLOCK (LEFT SIDE OF ENGINE COMPT) WHT WIRE WHT/BLK WIRE YEL WIRE YEL/BLK WIRE

BLK WIRE BRN WIRE COMPRSR RELAY (DIAGRAM 2 OF 3) COOLING FAN DIODE 1 COOLING FAN DIODE 2 DK BLU WIRE DK BLU/WHT WIRE DK GRN WIRE EXCEPT 6.0L FAN CNTRL RELAY FAN FUSE 68 FAN HI RELAY FAN LO RELAY FAN RELAY FAN-1 FUSE 60 FAN-2 FUSE 62 GRY WIRE GRY/BLK WIRE HOT AT ALL TIMES LEFT AIR TEMPERATURE ACTUATOR (BOTTOM LEFT OF HVAC MODULE) LOGIC LEFT COOLING FAN (EXCEPT 6.0L) (LEFT FRONT OF ENGINE COMPT) LOGIC LOGIC B+ GND LOWER LEFT AIR TEMPERATURE SENSOR (LEFT SIDE OF HVAC MODULE) LOWER RIGHT AIR TEMPERATURE SENSOR (LOWER LEFT OF HVAC MODULE) LT BLU WIRE LT BLU/BLK WIRE LT GRN WIRE MODE ACTUATOR (LEFT END OF HVAC MODULE) ORG/BLK WIRE PPL PWR/ TRN RELAY RECIRCULATION ACTUATOR (TOP RIGHT SIDE OF HVAC MODULE) RIGHT AIR TEMPERATURE ACTUATOR (TOP MIDDLE OF HVAC MODULE) LOGIC RIGHT COOLING FAN (RIGHT FRONT OF ENGINE COMPT) TAN WIRE TO A/C UNDER- HOOD FUSE BLOCK (LEFT SIDE OF ENGINE COMPT) WHT WIRE WHT/BLK WIRE YEL WIRE