Conditions for Setting the DTC: P2728
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.
The TCM detects an internal electrical performance malfunction of the clutch PC solenoid 5 control circuit and the actual 1-2-3-4 clutch pressure does not equal the commanded 1-2-3-4 clutch pressure for 5 seconds.