Lexus 2013 GS 350 Owner's Manual page 481

5-4. Using the hands-free phone system (for cellular phone)
Speaking on the phone
The following screen is displayed when speaking on the phone.
To adjust the incoming call volume
■
Select "-" or "+", turn the "PWR/VOL" knob, or use the volume switch
on the steering wheel.
To prevent the other party from hearing your voice
■
Select "Mute".
GS350_U (OM30C34U)
I n f o r ma t i o n P r o v i d e d b y :
5