Action Taken When the DTC Sets

WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

P0976

DTC P0976 is a Type A DTC.
The TCM defaults the transmission to 3rd gear or reverse gear.
The TCM forces the torque converter clutch (TCC) OFF.
The TCM commands maximum line pressure.
The TCM freezes transmission adaptive functions.
The TCM enables Torque Management.
The TCM inhibits TAP Up/Down function.
The TCM inhibits manual shifting of forward gears.

P0977

DTC P0977 is a Type B DTC.
The TCM inhibits 1st gear.