Toyota 2015 Sienna Manual page 149

Active head restraints
When the occupant's lower back
presses against the seatback dur-
ing a rear-end collision, the head
restraint moves slightly forward
and upward to help reduce the
risk of whiplash on the seat occu-
pant.
■
Active head restraints
Even small forces applied to the seatback may cause the head restraint to
move. When a locked head restraint is pushed up forcibly, the head restraint
inner structure may appear. This does not indicate a problem.
Inner structure
SIENNA_OM_01999-08001_(U)
3-3. Adjusting the seats
During
rear-end
collision
149
ITN13N065
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