Conditions for Setting the DTC

WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The ECM detects that the A/C pressure is less than 1 psi (0.01 volt) sets DTC P0532.
The ECM detects that the A/C pressure is more than 428 psi (4.92 volts) sets DTC P0533.