Alfa Romeo 4C Owner's Handbook Manual page 56

ACOUSTIC SIGNAL
When reverse gear is engaged and
there is an obstacle behind the vehicle,
an acoustic signal is emitted which
varies according to the distance of the
bumper from the obstacle.
The frequency of the acoustic signal:
❒ increases as the distance between
car and obstacle decreases,
culminating in a continuous acoustic
signal, when the distance is less
than approximately 30 cm;
❒ decreases if the distance from the
obstacle increases, until the signal
ceases entirely;
❒ remains constant if the distance
between car and obstacle remains
unchanged; if this situation concerns
the side sensors, the signal will
stop after approximately 3 seconds
to avoid, for example, indications
in the event of manoeuvres along a
wall.
If several obstacles are detected by the
sensors, only the nearest one is
considered.
52
INDICATIONS ON
DISPLAY
(for versions/markets, where provided)
When the sensors are activated, the
screen in fig. 54 appears on the display.
54
Obstacle presence and distance
information is therefore provided both
by the acoustic signal and the
instrument panel display.
The system indicates a detected
obstacle by displaying an arc in one or
more positions according to the
distance of the obstacle and its position
in relation to the car.
If an obstacle is detected in the rear
central area, the display shows all the
arcs in the rear central area, up to
the one that corresponds to the
position of the obstacle itself.
The signal is similar for obstacles in the
rear left or right area.
The arc that corresponds to the
position of the obstacle will flash.
The colour on the display depends on
the distance from and position of the
obstacle.
The car is close to the obstacle when
the display shows a single constant arc
and emits a continuous sound.
If there are several obstacles, the
closest one is indicated.
FAULT INDICATION
A0L0044
Parking sensor failures, if any, will be
indicated when reverse is engaged by
the switching on of the
light on the instrument panel together
with the message on the display (see
"Warning lights and messages"
chapter).
GENERAL WARNINGS
45)
4)
When parking, take the utmost care
over obstacles that may be above
or under the sensor.
warning