Another software re-flash. Toyota recalls 2.4M Prius hybrid cars that could stall Toyota Recalls More Than 2 Million Vehicles Over Hybrid-System Fault - WSJ
It says prius gen 3 10-31-2014 to 4-17-2009. Software update of hybrid system needed. Problem reported is : hybrid system will not move into safe mode ( fail safe procedure) as needed and may cause total engine shut off at extreme cases while driving at high speed increasing chances of fatal crash. Also says brakes and steering will still be operational