In simple terms: a relay attack relays the smart key's radio signal to unlock the car from a distance; a CAN invader illicitly accesses the car's communication network to unlock and start it; and a code grabber copies the key's signal. All of them share one thing—the car can be opened and driven without holding the real key.

We match countermeasures to each method: for network-based takeover, systems that alert immediately and prevent starting; for signal relay, measures that stop the doors opening at all. The best answer depends on your car's year and equipment, so we propose the ideal combination after diagnosis.