Mazda CX-9 2016 Owner's Manual page 317

Parking Sensor Warning Beep
The beeper sounds as follows while the system is operating.
Rear Sensor
Distance detection area
Farthest distance
Far distance
Middle distance
Close distance
*1 The rate at which the intermittent sound beeps increases as the vehicle approaches the obstruction.
Distance between vehicle and obstruction
Approx. 150—60 cm (59.0—23.6 in)
Approx. 60—45 cm (23.6—17.7 in)
Approx. 45—35 cm (17.7—13.7 in)
Within approx. 35 cm (13.7 in)
Parking Sensor System
Beeper sound
Slow intermittent sound
Medium intermittent sound
Fast intermittent sound
Continuous sound
When Driving
*1
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