Conditions for Running the DTC

WARNING: This page is about a different car, the 2007 GMC Sierra, 2007 GMC Cab & Chassis Sierra, 2007 Chevrolet Silverado, and 2007 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

DTCs P0545, P0546, P2032, P2033 are not set.
The engine has been OFF for greater than 5 hours.
The engine is running.
The ambient temperature is greater than 10°C (50°F).
DTC P20E2 runs once per key cycle within the above enabling conditions.