CITROËN C4 Picasso Owner's Handbook Manual page 188

Driving
To deactivate the system, press
this button again; its indicator
lamp goes off as well as the
associated indicator in the
instrument panel.
The state of the system remains in memory on
switching off the ignition.
The system is automatically deactivated
when towing with a towbar approved by
CITROËN.
188
Operating fault
In the event of a fault, the warning
lamp flashes then goes off.
Have it checked by a CITROËN dealer or a
qualified workshop.
The system may suffer temporary
interference in certain weather
conditions (rain, hail...).
In particular, driving on a wet surface
or moving from a dry area to a wet area
can cause false alerts (for example, the
presence of a fog of water droplets in
the blind spot angle is interpreted as a
vehicle).
In bad or wintry weather, ensure that
the sensors are not covered by mud, ice
or snow.
Take care not to cover the warning zone
in the door mirrors or the detection
zones on the front and rear bumpers
with adhesive labels or other objects;
they may hamper the correct operation
of the system.
High pressure jet wash
When washing your vehicle, direct the
lance at least 30 cm away from the
sensors.