Okay, they're not actually a secret, but they are largely unknown. If your Lexus has voice activation, there's more you can do with it than control Bluetooth and navigation.
In this latest Driver Quick Tip, Lexus magazine shows you how to control your Lexus model’s audio and climate systems with your voice. It’s actually pretty simple, and it does away with a lot of button-pushing while on the road.
 The navigation system is designed to assist in locating an address or point of interest. Discrepancies may be encountered between the system and your actual location. Road system changes may affect the accuracy of the information provided. Rely on your common sense to decide whether to follow a specified route. Detailed coverage not available in every city or roadway. Periodic updates available at an additional cost. See your Navigation System Owner’s Manual for further details.