See also:

Safety
Both the coupe and convertible have front airbags plus side-impact airbags built into the front seats. As required of all 2012 models sold in the U.S., the 640i has standard antilock brakes and an ...

Switching off automatically
The system switches off and the LED goes out: After approx. 33 ft/10 m when driving forward. Above approx. 9 mph/15 km/h when driving forward. Switch on the system again if necessary. ...

Automatic deactivation during forward travel
The system switches off when a certain driving distance or speed is exceeded. Switch the system back on if necessary. ...