In this video, we learn how to use the smart key for the 2010 Prius. You can use this just like any other keyless entry system. Press the lock button to lock the doors and the unlock button to unlock the doors. When you press unlock once it unlocks the drivers door, if you press it twice within 3 seconds, it unlocks all the door. After 60 seconds, the Prius will automatically lock itself. Press the red alarm key if you need to draw attention to yourself in an emergency situation. Make sure you are near the car when you want to unlock it, or it won't work.