represents active main beam.The function can start while driving in the dark when the car's speed is approx. 20 km/h (approx. 12 mph) or higher. The function can also take streetlights into account. When the camera sensor no longer detects any oncoming car or car in front, main beam is switched on again after about a second.
Activate active main beam
Active main beam is activated and deactivated by turning the left-hand stalk switch to position . The rotating ring then returns to position 
. When active main beam is activated, the symbol illuminates with a white glow in the driver display. When main beam is activated, the symbol shines blue.
If active main beam is deactivated while main beam is on, the lighting is immediately reset to dipped beam.
Active main beam does not need to be reactivated every time the car is started.
Adaptive functionality
For cars with LED1 headlamps*, active main beam has adaptive functionality2. In this case, unlike what happens during conventional dimming, the light beam continues to illuminate with main beam on both sides of oncoming traffic or vehicles ahead – only the part of the light beam that points directly to the vehicle is dimmed.
The main beam is partly dimmed, i.e. if the light beam shines with slightly more than dipped beam, the symbol in the driver display shines blue.
On motorways or at high speed, the system may change from adaptive to automatic functionality.
Limitations for active main beam
The camera sensor on which the function is based has limitations.
If this symbol is shown in the driver display, together with the message Active High Beam Temporarily unavailable, then switching between main and dipped beam must be performed manually.
The same applies if this symbol is shown together with the message Windscreen sensor blocked See Owner's manual.
Active main beam may be temporarily unavailable e.g. in situations with dense fog or heavy rain. When active main beam becomes available again, or the windscreen sensors are no longer blocked, the message goes out and the symbol illuminates.
Warning
Active main beam is an aid for using the optimum beam pattern when conditions are favourable.
The driver always bears responsibility for manually switching between main and dipped beam when traffic situations or weather conditions so require.