2011 Toyota Prius Owners Manual - Page 365

3-3. Using the hands-free system (for cellular phone) n Steering wheel Volume The voice guidance volume cannot be adjusted by using this button. ITO33P104 Press: Voice command system on Press and hold: Voice command system off Hands-free phone system off/ends a call/refuses a call Hands-free phone system on/starts a call 3 Interior features 341 PRIUS_U (OM47685U) DVD