Understanding Smart Car Key Systems

With more than one method to unlock modern vehicles, it’s important to understand the options and which techniques apply to your car.

Key Cards / NFC Passes

Used by: Tesla, Rivian, and Lucid

A car key card or key fob is no bigger than a credit cards, allowing you access to your vehicle. Using something called Radio-Frequency Identification (RFID) or Near Field Communication (NFC), it allows you to access the vehicle.

Mobile App Access

Used by: EV makers now integrate car unlocking/starting into smartphone apps

Mobile app access acts as a digital key, using Bluetooth, NFC, or Ultra-Wideband (UWB) to communicate directly with the car. Manufacturer apps can also send commands over longer distances via the internet and cellular networks. The vehicle verifies your device with encrypted authentication protocols before unlocking, keeping the connection secure.

Digital Key (Bluetooth & UWB)

Used by: Car brands use “digital keys” that are stored in Apple Wallet or Android Wallet.

Using NFC, Bluetooth and Ultra-Wideband (UWB), your phone can communicate with the car in different ways: UWB enables passive entry so the vehicle can unlock automatically as you approach, while NFC lets you tap your phone on the door handle or inside the car to lock, unlock, or start the engine.

Smart Key Fobs 

Uses: available as backup but often encrypted with rolling codes and remote features

Smart key fobs use radio frequency (RF) signals to communicate with a car’s engine control unit (ECU). This allows drivers to lock or unlock doors and start the engine without inserting a physical key. When the fob is within range, it transmits a signal to the car, and if the encrypted code matches, the system unlocks the doors or enables push-button ignition.