Dodge Charger SRT Hellcat 392 2016 Owner's Manual page 127

Rear Detection Zones
When the vehicle is started, the BSM warning light will
momentarily illuminate in both outside rear view mirrors
to let the driver know that the system is operational.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 125
The BSM system sensors operate when the vehicle is in
any forward gear or REVERSE and enters stand-by mode
when the vehicle is in PARK.
BSM Warning Light
3