To activate/deactivate:

press the button.

When the distance warning function is activated, the symbol appears in the multifunction display.

Also, the status appears in the Status overview of the Assistance menu.

At speeds up to approximately 30 km/h, the multifunction display in vehicles with Active Parking Assist first shows the status indicator. Only from a speed of approximately 30 km/h does the multifunction display show the symbol instead of the status indicator.