Tap on the BLIS button in the function view.
BLIS is activated/deactivated - a green/grey indicator is shown in the button.
If BLIS is activated when starting the engine, the function is confirmed by the door mirror indicator lamps blinking once.
If BLIS was deactivated when the engine was switched off, it will continue to be deactivated when the engine is next started and no indicator lights will then be illuminated.