Adjusting the height: electrical
The head restraints on the left and right rear passenger seats extend automatically whenever a passenger in the rear seat fastens his or her safety belt.

In addition, the height of the head restraint can be adjusted electrically.
Extending the head restraint
To prevent possible personal injury and property damage, always ensure that the area above the head restraints is clear and unobstructed before extending them upward.
The height adjustment of the head restraint is deactivated when the safety switch for the rear windows, has been pressed.
See also:
Tire inflation pressure values over 100 mph/160 km/h
320i
328i
335i
...
Adjusting the height: electrical head
restraints
Adjusting the height: electrical head
restraints
Adjusting electrically. ...
All around the steering wheel
1 Rear window safety switch
2 Power windows
3 Exterior mirror operation
4
Lane departure warning
Collision warning
5 Lamps
Front fog lamps
Parking lamps
...
