2010 Toyota Highlander Owners Manual - Page 1142

5-2. Steps to take in an emergency *1 : Open door warning buzzer: The open door warning buzzer sounds to alert one or more of the doors is not fully closed (with the vehicle having reached a speed of 3 mph [5 km/h]). *2 : Driver's and front passenger's seat belt reminders: The driver's and front passenger's seat belt reminders sound to alert the driver and front passenger that his or her seat belt is not fastened. These buzzers sound for 10 seconds after the vehicle has reached a speed of at least 12 mph (20 km/h). Then, if the seat belt is still unfastened, the buzzer will sound in a different tone for 20 more seconds. *3 *4 : Vehicles without navigation system : Vehicles with navigation system