2011 Toyota Sienna Owners Manual - Page 219

1-3. Adjustable components (seats, mirrors, steering wheel) Seat belt pretensioners (front seats) The pretensioner helps the seat belt to quickly restrain the occupant by retracting the seat belt when the vehicle is subjected to certain types of severe frontal collision. The pretensioner may not activate in the event of a minor frontal impact, a side impact or a rear impact. 1 Before driving Pre-collision seat belts (front seats of vehicles with pre-collision system) If the pre-collision sensor detects that a collision is unavoidable, the pre-collision system will retract the seat belt, thus enhancing the effectiveness of the seat belt pretensioner in a crash. The same will happen if the driver makes an emergency braking or loses control of the vehicle. (→P. 307) 125