Action Taken When the DTC Sets

WARNING: This page is about a different car, the 2016 Cadillac ATS. However, it is still accessible from the selected car via links, so may be relevant.

P0776 or P0777

P0776 or P0777 are Type A DTCs.
TCM disables transmission adapts learning and freezes current adapt values.
TCM commands default shift pattern and ignores all other shift requests.
TCM inhibits Tap Up/Tap Down.
TCM inhibits TCC.
TCM requests the ECM to disable powertrain braking.
TCM requests the ECM to disable neutral idle.
TCM requests the ECM to disable auto grade braking.
TCM requests the ECM to disable auto stop function.
Transmission shifts to 6th gear, if P0776 sets.
Transmission shifts to 2nd gear, if P0777 sets.
Transmission reverse gear is available.