Toyota 2010 Prius Owner's Manual page 113

1-4. Adjustable components (seats, mirrors, steering wheel)
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Adjusting the height of the belt (front seats)
Seat belt pretensioners (front seats)
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. 249)
86
Down
Up
Move the height adjuster up
and down as needed until you
hear a click.
The pretensioner helps the seat
belt to quickly restrain the occu-
pant by retracting the seat belt
when the vehicle is subjected to
certain types of severe frontal
collision.
The pretensioner may not acti-
vate in the event of a minor frontal
impact, a side impact or a rear
impact.