CITROEN DS3 Owner's Handbook Manual page 56

Front demist - defrost
These markings on the control panel indicate the control positions for rapid demisting or
defrosting of the windscreen and side windows.
system
Put the temperature and air flow controls to
the dedicated marked position.
Put the air intake control to the "Exterior air
intake" position
(manual control to the right or electric
control with indicator lamp off).
Put the air distribution control to the
"Windscreen" position.
conditioning system
Put the temperature and air flow controls to
the dedicated marked position.
Put the air intake control to the "Exterior air
intake" position
(manual control to the right or electric
control with indicator lamp off).
Put the air distribution control to the
"Windscreen" position.
Switch on the air conditioning by pressing
the "A/C" button; the associated green
warning lamp comes on.