2008 Chevrolet Chevy Express G3500, Van Passenger ExtendedFACTORY OEM SERVICE PROCEDURE

HVAC Control Assembly X3

Fig 1: HVAC Control Assembly X3 Connector End View
GM62450Courtesy of GENERAL MOTORS CORP.
HVAC Control Assembly X3

Pin Wire Circuit Function
A 0.8 RD/WH 4440 Battery Positive Voltage (C49/DE5/DE7)
B 0.35 BN 341 Ignition Voltage
C 0.5 BK 550 Ground
D 0.35 WH 193 Rear Defog Relay Control (C49/DE5/DE7)
Connector Part Information 
  • OEM: 12052856
  • Service: 12125636
  • Description: 4-Way F Metri-Pack 280 Series (BK)
Terminal Part Information 
  • Pins: A
  • Terminal/Tray: 12066214/2
  • Core/Insulation Crimp: See Terminal Repair Kit
  • Release Tool/Test Probe: 12094430/J-35616-4A (PU)
  • Pins: B-D
  • Terminal/Tray: 12034046/2
  • Core/Insulation Crimp: E/A
  • Release Tool/Test Probe: 12094430/J-35616-4A (PU)
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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