Jeep Wrangler2018 Owner's Manual page 221

Warning Light Location
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.
Side Monitoring
SAFETY 219
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