Aston Martin One-77 2010 Owner's Manual page 76

The level of brightness can be reduced by using the
rotary control (B). If the brightness level has been
adjusted, the twilight and night time brightness level
will return to the previous setting on the rotary control,
each time the sensor picks up the twilight hours.
4.18
Push the rotary control in and release to enable the
control. Push in and release to lock the control.