Test Description

WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

4) - The HVAC control module is inoperative when the module does not respond to an operator control request.
8) - If no condition found with all conditions listed then compare door travel to known good vehicle.
14) - The voltage will vary between 0-5 volts during normal operation. Ensure to observe the air temperature actuator driveshaft and the volt meter when jumping the control circuit with 5 volt reference and the ground circuits. The air temperature actuator and the HVAC control assembly connectors must be connected during this step.

Fig 1: Too Cold In Vehicle Diagnosis (Steps 1-7)

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Fig 2: Too Cold In Vehicle Diagnosis (Steps 8-14)

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Fig 3: Too Cold In Vehicle Diagnosis (Steps 15-24)

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