A lot of people have been telling me that I should add RFID to my engine start button project. That’s exactly what I did. I’m using an Arduino Nano connected to a RC522 RFID reader/writer. When the Nano recognizes a scanned RFID tag, it sends a code via serial to the ATMega328 that controls the ignition/accessories/starter motor. When the ATMega328 receives the code, it enables the engine start functionality. If no RFID tag is scanned or if an incorrect tag is scanned, pressing the engine start button will not start the engine.