Conditions for Setting the DTC: P0777
WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
The TCM detects an incorrect off-going clutch gear ratio, or tie-up, when the 3-5-R clutch is commanded OFF for 1.2 seconds and the transmission input shaft speed is 40 RPM or less from the anticipated input shaft speed.