CITROEN DS3 Handbook page 26

Warning/indicator lamp is on
fixed.
diesel engine
pre-heating
fixed.
Parking brake
fixed.
Stop & Start
flashes for a few
seconds, then goes
off.
Cause
The key is at position 2 (ignition on) in
the ignition switch.
The parking brake is applied or not
properly released.
When the vehicle stops (red lights,
traffic jams, ...) the Stop & Start system
has put the engine into STOP mode.
STOP mode is temporarily
unavailable.
or
START mode is invoked
automatically.
Action / Observations
Wait until the warning lamp goes off before starting.
The period of illumination of the warning lamp is
determined by the ambient conditions (up to about
thirty seconds in very low temperatures).
If the engine does not start, switch the ignition off and
then on, wait until the warning lamp goes off again,
then start the engine.
Release the parking brake to switch off the warning
lamp, keeping your foot on the brake pedal.
Observe the safety recommendations.
For more information on the parking brake, refer to the
corresponding section.
The warning lamp goes off and the engine restarts
automatically in START mode, as soon as you want to
move off.
For more information on special cases with STOP
mode and START mode, refer to the "Stop & Start"
section.