Dodge Durango SRT 2018 Owner's Manual page 187

Park Assist Ready Single 1/2 Second Tone Slow Tone For Rear Only
The system will indicate a detected obstacle by
showing a single arc in the left and/or right front
or rear regions based on the object's distance
and location relative to the vehicle.
If an object is detected in the left and/or right
rear region, the display will show a single arc in
the left and/or right rear region and the system
will produce a tone. As the vehicle moves closer
to the object, the display will show the single arc
moving closer to the vehicle and the tone will
change from a single 1/2 second tone to slow, to
Slow Tone Fast Tone For Rear Only
fast, to continuous.
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