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HOMESERVICE MANUALSCHEVROLET2008CHEVY EXPRESS G2500, VAN CARGO, 6.6 6REPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 2698 (WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - 3 OF 5)HVAC CONTROL MODULE X1
2008 Chevrolet Chevy Express G2500, Van Cargo, 6.6 6

HVAC Control Module X1

2008 Chevrolet Chevy Express G2500, Van Cargo, 6.6 6SECTION HVAC Control Module X1
WARNING: This page is about a different car, the 2008 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: HVAC Control Module - X1 Connector End View
GM255037Courtesy of GENERAL MOTORS CORP.
HVAC Control Module X1

Pin Wire Circuit Function
A1 0.35 RD/WH 340 Battery Positive Voltage
A2 0.35 YE 6817 LED Backlight Dimming Control
0.35 YE 6817 LED Backlight Dimming Control
A3 - - Not Used
A4 0.35 L-GN 1478 Coolant Level Switch Signal
A5 0.35 BN 247 Medium Blower Motor Control
A6 - - Not Used
A7 0.35 PU/WH 5203 Air Quality HC Sensor Signal (K14)
A8 0.35 L-GN/BK 735 Outside Ambient Air Temperature Sensor Signal
A9 0.35 GY 731 A/C Refrigerant Low Temperature Sensor Signal
A10 0.35 L-BU/BK 590 Solar Sensor Driver Signal
A11 0.35 WH 278 Ambient Light Sensor Signal
A12 0.35 GY 705 5-Volt Reference
B1 0.35 PK 1539 Run/Crank Ignition 1 Voltage
B2-B4 - - Not Used
B5 0.35 D-GN 5060 Low Speed GMLAN Serial Data
B6 0.35 GY/BK 754 Blower Motor Speed Control
B7 0.35 L-GN/WH 6845 Air Quality NOX Sensor Signal (K14)
B8 - - Not Used
B9 0.35 D-GN 734 Inside Air Temperature Sensor Signal
B10 0.35 GY 1548 Passenger Solar Sensor Signal
B11 0.35 BK/WH 451 Ground
B12 0.35 YE 61 Outside Ambient Temperature Sensor Low Reference
Connector Part Information 
  • OEM: 12160778
  • Service: 12160778
  • Description: 24-Way F Micro-Pack 100 Series (BN)
Terminal Part Information 
  • Terminal/Tray: 12146447/3
  • Core/Insulation Crimp: E/C
  • Release Tool/Test Probe: 12031876-1/J-35616-6 (BN)
RENDER: 1.0x

NO RELATED

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