Conditions for Setting the DTC: P0872
WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The TCM detects that the TFP switch 3 signal voltage remains low, 0 volts when the 2-6 clutch is commanded ON for 5 seconds.