See also:

Bluetooth® audio operation
NOTE Depending on the connected device, it may not activate as per the following items or not work smoothly. ...

To increase the speed (by accelerator pedal)
1. Depress the accelerator pedal to accelerate the vehicle to the desired speed. 2. Press the “RES/SET” switch to the “SET” side once. Now the desired speed is set and the vehicle will keep running ...

Volume control switch
Press the switch to the “+” side to increase the volume. Press the switch to the “−” side to reduce the volume. A number indicating the volume will be shown on the audio display. ...