You can also use the iDrive Controller to turn on the high beams by doing the following: Press the iDrive button on the center console. Use the controller to navigate to the "Lighting" menu. Select "High-Beam Assistant" and turn it on. Press the iDrive button again to exit the menu.
The high beam assistant automatically turns on high beams when the road is clear and turns them off when an oncoming vehicle is detected.
Use can also turn on auto high beams with a button on the stalk on the left side of the steering column.