Ram Trucks 2011 3500 - Owner Manual - Manual (Page 142)

The system will indicate a detected obstacle by showing
three solid arcs and will produce a one-half second tone.
As the vehicle moves closer to the object the EVIC
display will show fewer arcs and the sound tone will
change from slow, to fast, to continuous.
Park Assist System Off Slow Tone
140 UNDERSTANDING THE FEATURES OF YOUR VEHICLE