Switching the microphone to mute
When a call is active, the microphone can be muted.
1. "Telephone"
2. "Active calls"
3. 
"Microphone
mute"
A microphone that has been switched to mute is automatically reactivated:
▷ When a new connection is established.
▷ When switching between call parties.
See also:
Checking the engine oil level
Your car is equipped with an electronic engine
oil level check.
Requirements
▷ The engine must be running and warm after
the vehicle has been driven for at least
6.2 miles/10 km.
▷ ...
Owner's Manual for Vehicle
Thank you for choosing a BMW.
The more familiar you are with your vehicle, the better control you
will have on the road. We therefore strongly suggest:
Read this Owner's Manual before starting off ...
Switching off automatically
The system switches off and the LED goes out:
▷ After approx. 165 ft/50 m when driving forward.
▷ After approx. 22 mph/35 km/h when driving
forward.
Switch on the system again if nece ...