2010 Toyota Sienna Owners Manual - Page 237
2010 Toyota Sienna Manual
Page 237 highlights
2 -4 . U sing ot he r driving syst e m s I nt uit ive pa rk ing a ssist (if e quippe d) The distance to obstacles measured by the sensors is communicated via the indicator and a buzzer when parallel parking or maneuvering into a garage. Always check the surrounding area when using this system.