Conditions for Setting the DTC
WARNING: This page is about a different car, the 2004 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
The HVAC control module determines that the voltage applied to the input for the air temperature sensor is less than 0.09 V, for B0332 and B0337, or more than 4.9 V, for B0333 and B0338.