Aston Martin DB 9 2010 Manual page 36

Push both the memory button (M) and the desired setting button (1,
2 or 3) simultaneously, then release, to memorize the configuration.
By repeating these
steps and pressing an
unused button (1, 2 or
3), a second and third
driving position can be
stored in the memory.
When making
adjustments to a set driving position, reset the new position in the
same memory channel. The previous memory is erased when a new
driving position is entered.
3.6
Recalling a Memorized Position
Once in the seat press and hold button 1, 2 or 3 (depending on which
position required) until all movement is stopped.
The seat and door mirrors (when adjusting the driver's seat) move to
the programmed position. If the button is released all movement will
stop, press and hold again to continue movement.
Memory Using the Vehicle Key
When the vehicle is locked using the vehicle key, the driver's seat and
both door rear view mirrors will remember their positions. The next
time the vehicle is opened using the same vehicle key, the seat and
door rear view mirrors will move to the memorized position.
The seats and door rear view mirrors only move if they have been
moved previously, i.e. the spare vehicle key has been used to open
and close the vehicle.
Emergency Stop
If the seat accidentally begins to move, press any seat control button
to stop the seat.