An Arduino Nano controls two relays which in turn can turn the car on, start it, and turn it off. Instead of adding a button for “push to start” he opted for a 13.56MHz RFID module.

His solution takes an off-the-shelf high-powered reader, (such as the HID MaxiProx 5375), and makes it amazingly portable by embedding 12 AA batteries and a custom PCB using an Arduino Nano to ...