It operates according to an ultrasound sonar principle: four ultrasound transducers are located inside the rear bumper. They send signals to a control unit which processes this information determining the distance of possible obstacles.A speaker controlled by the control unit emits an intermittent sound, proportional to the distance of the obstacle detected.The control unit is activated with reverse gear engaged: in these conditions, it energizes the transducers and sends them a signal request, receiving the response signals.The control unit emits a signal with an intermittent sound through the special speaker: the frequency of this sound increases gradually as the bumper approaches an obstacle: when the distance calculated goes below 25 cm, the sound becomes high-pitched and constant.If the distance of the obstacle detected increases, or if the driver disengages reverse gear, the sound stops. If the distance of the obstacle detected remains constant, the sound stops after about 3 seconds. For more details and information on the operation of the system, Characteristic of working principle 5580H DISPOSITIVO RILEVAMENTO OSTACOLI IN PARCHEGGIO . The control unit is located inside the luggage compartment, on the right hand side; there is a buzzer next to the contorl unit. The system receives a power supply from the reversing lights circuit ( Vedere E2022 LUCI RETROMARCIA
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