2010 Toyota Highlander Navigation Manual - Page 127

OTHER FUNCTIONS INFORMATION D Talk alternately with the other party on the phone. If you talk at the same time, the voice may not reach each other. (It is not a malfunction.) D Keep the volume of receiving voice down. Otherwise, echo is coming up. When you talk on the phone, speak clearly towards the microphone. D In the following situations, your voice may not reach the other party. D Driving on unpaved road. (Too much road noise.) D Driving at high speed. D Windows are open. D If air−conditioning vents are turned towards the microphone. D The sound of the air−conditioning fan is loud. By pushing the telephone switch above, you can receive a call or hang up without taking your hands off the steering wheel. "Microphone You can use the microphone above when talking on the phone. The other party's voice outputs from the driver's speaker. When the received calls or received voice outputs, the audio from the Audio/video system or voice guidance from the Navigation system will be muted. 128