PARKING SENSOR - Description

Description

The parking assistance system provides the driver with information whilst reversing relating to distance when approaching obstacles which are behind the vehicle, which could be outside the driver's field of view.

The information that there is an obstacle and its distance is transmitted to the driver by means of acoustic signals whose frequency varies according to the distance of the vehicle from the obstacle.

An electronic control unit activates and controls the operation of the sensors located in the rear bumper, processing the signals received and activating the acoustic signal inside the instrument panel.

The system is activated when reverse gear is engaged: under these conditions the control unit energizes the transducers and sends them a request signal, receiving response signals.

The sensors use ultrasound technology and act as intelligent transmitters/receivers with triangulation technique: this allows improved detection in critical situations or where small obstacles are present. The impulses emitted are reflected by any obstacles; the transducers therefore receives an echo which is converted into a digital signal and sent to the electronic control unit.

The distance of the obstacle is signalled by sounds with intermittent impulses: the frequency of this signal increases gradually as the bumper approaches an obstacle: when the distance calculated is less than 30 cm, the sound becomes high pitched and constant; the acoustic signal, on the other hand, ceases when the distance of the obstacle increases.

For more details and information on the operation of the system, Characteristic of working principle 5580H parking obstacle detection device

The control unit has an autodiagnostic function: when it is switched on the control unit carries out an initial test on the sensors.which are then continuously diagnosed during the operation of the system.

A fault with only one sensor inhibits the operation of the entire system: in this case, the system excludes itself and sends a fault message, the failure status is signalled to the instrument panel lighting up the dedicated warning light and sending a suitable acoustic warning.

The signal that the reversing light has been switched on See E2022 REVERSING LIGHTS is managed by the Body Computer which forwards this information to the parking sensor control unit via the CAN network.

Rear obstacles are not signalled if there is a trailer See E2050 TRAILER WIRING.

The system is supplied via a circuit protected by a specific fuse in the underfacia control unit.