Volvo 2008 V70 Owner's Manual page 168

Visual indicator
The audio system's display gives an overview of the vehicle's position in relation to a detected object.
The markers in the display indicate that one or more of the four sensors has detected an object. The greater the number
of markers, the closer the vehicle is to the object.
Display in a vehicle with rear park assist only. Here, an object has been detected by both of the right rear sensors.
Display in a vehicle with both front and rear park assist. The solid marker in this example indicates that an object is
closer than approximately 1 foot (30 cm) to the right front sensor.
Display in a vehicle with both front and rear park assist. Reverse gear is selected and no objects have been detected
in front of or behind the vehicle.
Audible signal
The Park Assist system uses an intermittent tone that pulses faster as you come close to an object, and becomes
constant when you are within approximately 1 ft (30 cm) of an object in front of or behind the vehicle (example 2 in
the illustration). If there are objects within this distance both behind and in front of the vehicle, the tone alternates
between front and rear speakers.
If the volume of another source from the audio system is high, this will be automatically lowered.
Rear park assist
The distance monitored behind the vehicle is approximately 5 ft (1.5 m). The audible signal comes from the rear
speakers.
The system must be deactivated when towing a trailer, carrying bicycles in a rear-mounted carrier, etc, which could
trigger the rear park assist system's sensors.
NOTE