Action Taken When the DTC Sets

WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

DTCs P2719, P2720, and P2721 are Type A DTCs.
The TCM defaults the transmission to a limited shift pattern utilizing 2 forward gears and reverse based on the default detected.
The TCM commands maximum line pressure.
The TCM freezes transmission adaptive functions.