CITROËN DS 4 Handbook page 44

Black panel (comfortable
night driving display)
When driving at night, it allows certain
instrument panel displays to be switched off so
as to reduce visual fatigue for the the driver.
The essential driving information, such as
the vehicle speed, warning lamps, automatic
gearbox gear selected, cruise control or speed
limiter information, remains on in the instrument
panel.
F With the vehicle lighting on,
press this button again to
activate the function.
F Press this button again to
deactivate the function.
Touch screen tablet
You can returns to the current display
at any time by pressing the black
screen or one of the menu buttons.
In automatic illumination of headlamps
mode, the "Black panel" function is
automatically deactivated once the
ambient light level attains an adequate
level.
Customising the instrument
panel colours
In the instrument panel, you can change the
colour of its dials (button A) independently from
that of the screens (button B).
There are five colour variants, from white to
blue.
F Press the appropriate button as many
times as needed to obtain the desired
colour.