The rear seats have head restraints in the outboard seating positions that can be lowered for better visibility when the rear seat is unoccupied.

To lower the head restraint, press the button, located on the top of the seatback, and push the head restraint down.
When an occupant is in the seat, always return the head restraint to the upright position. Pull the head restraint up and push it rearward until it locks into place. Push and pull on the head restraint to make sure that it is locked.
Rear outboard head restraints are not removable.
Seat Adjustment
Power Seat Adjustment
DTC B1825, B2355, B2365, OR B2375: Driver seat front vertical position
sensor
DTC C1589: Multi-axis acceleration sensor/steering wheel angle sensor supply
voltage circuit performance - bias level out of range