See also:

Malfunction
In the event of a failure or malfunction of the parking brake, secure the vehicle against rolling using a wheel chock, for example, when leaving it. ...

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 automatic ...

Releasing the parking brake manually
In the event of an electrical power loss or electrical malfunction, you can release the parking brake manually. Secure the vehicle against rolling Before releasing the parking brake manually, ...