This indicator light illuminates:
When you select "SPORT" mode as drive mode.
Hyundai Sonata LF 2014-2019 Owners Manual: Instrument Cluster Control
Adjusting instrument cluster illumination
When the vehicle's parking lights or headlights are on, press the illumination
control button to adjust the brightness of the instrument panel illumination.
When pressing the illumination control button, the interior switch illumination
intensity is also ...
Hyundai Sonata LF 2014-2019 Service Manual: Power Door Mirror Actuator Components and Components Location
Components
1. BSD Indicator2. Side repeater lamp3. Puddle lamp
...