Test Description

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 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 in the diagnostic table.

8. This step ensures that the lower air temperature sensors operate properly. The LH and RH Heater Duct Actual parameter count values should lower as the air temperature of the ducts get warmer. If there is a high resistance in either of the air temperature sensors circuits or the sensor itself then the count value of the effected sensor would remain high.
9. This step ensures that the upper air temperature sensors operate properly. The LH and RH AC Duct Actual parameter count values should lower as the air temperature of the ducts get warmer. If there is a high resistance in either of the air temperature sensors circuits or the sensor itself then the count value of the effected sensor would remain high.
11. This action ensures that the internal fan of the inside air temperature sensor assembly is providing air flow across the internal sensor.
15. Use the following table to determine that the recorded scan tool values are within range for the recorded probe temperatures.

Fig 1: Scan Tool Values & Temperature Ranges
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Fig 2: Too Cold In Vehicle (Steps 1-8)

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Fig 3: Too Cold In Vehicle (Steps 9-14)

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Fig 4: Too Cold In Vehicle (Steps 15-19)

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Fig 5: Too Cold In Vehicle (Steps 20-28)

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