2010 Toyota Prius Owners Manual - Page 271
2010 Toyota Prius Manual
Page 271 highlights
2 -4 . U sing ot he r driving syst e m s Driving a ssist syst e m s To help enhance driving safety and performance, the following systems operate automatically in response to various driving situations. Be aware, however, that these systems are supplementary and should not be relied upon too heavily when operating the vehicle.