Chrysler 2013 Country - Owner Manual - Manual (Page 144)

The BSM system monitors the detection zone from three
different entry points (side, rear, front) while driving to
see if an alert is necessary. The BSM system will issue an
alert during these types of zone entries.
Entering From The Side
Vehicles that move into your adjacent lanes from either
side of the vehicle.
BSM Warning Light
Side Monitoring
142 UNDERSTANDING THE FEATURES OF YOUR VEHICLE