Comfort and Convenience
The on-board computer is always active once the ignition is on; the multifunction steering wheel buttons only change which readout is displayed, not whether the computer measures anything.
Safety and Driver Assistance
ESP works continuously while the car is moving, braking single wheels to correct a slide. ABS acts only during braking, releasing pressure so a locked wheel keeps turning and steering.
Multimedia and Connectivity
A USB socket carries data and charging current, but the head unit decides which file formats and storage layouts it will read, so some drives and players stay unrecognised.