See also:

Volume control
You can adjust the phone call volume, the voice volume and the voice guidance volume. Refer to “Volume control switch” F5-32. Adjustable level of each volume ...

Adjustable level of each volume
...

Car phone/cell phone and driving
Do not use a car phone/cell phone while driving; it may distract your attention from driving and can lead to an accident. If you use a car phone/cell phone, pull off the road and park in a safe plac ...