Action Taken When the DTC Sets

WARNING: This page is about a different car, the 2006 GMC Sierra, 2006 GMC Cab & Chassis Sierra, 2006 Chevrolet Silverado, and 2006 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The PCM assumes a 4WD low state if measured transfer case ratio is 2.65-2.76.
The PCM assumes a non-4WD low state if the measured transfer case ratio is 0.95-1.05.
The PCM freezes transmission adaptive functions.
The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame, California only, and Failure Records, California and Federal.
The PCM stores the DTC P2771 in PCM history during the second consecutive trip, California, or the first trip, Federal, in which the Conditions for Setting the DTC are met.