What is a Relay Attack on a Car?
A relay attack is a vehicle theft method where criminals use signal-amplifying devices to extend the range of your key fob, tricking the car into thinking the key is present so it unlocks and starts without the real key in hand.
A relay attack is one of the most common modern vehicle theft methods in Australia — and it's alarmingly simple. Two criminals work together: one stands near the target vehicle (usually in a driveway), and the other stands near the house with a signal amplifier. The first device picks up the faint signal from your key inside the house; the second amplifies and relays it to the car, which believes the key is nearby and unlocks automatically.
Once inside, the thief simply presses the start button. The car starts because it still detects the relayed key signal. The entire process can take under 60 seconds and leaves no visible damage to the vehicle — making relay attacks almost impossible to detect until the car is gone.
Relay attacks are most effective against vehicles with Passive Entry Passive Start (PEPS) systems — where you unlock by touching the door handle and start with a button press. This includes Toyota LandCruiser, Ford Ranger, BMW, Audi, Mercedes-AMG, Lexus NX and virtually every other modern keyless vehicle.
The only effective countermeasure against relay attack is a CAN-bus immobiliser like IGLA. IGLA requires a driver-set PIN before the engine will start — regardless of whether the vehicle is unlocked via relay signal. Even if the car is fully unlocked with a relayed or cloned key, the engine will not start without the PIN.
Common questions.
How do I know if my car is vulnerable to relay attack?
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Any vehicle with keyless (PEPS) entry is potentially vulnerable to relay attack. This includes most vehicles sold after 2015 with a key fob that unlocks the car by touch rather than a button press. If your car has a start button and automatically unlocks when you touch the door handle, it is relay-attack vulnerable.
Does a Faraday pouch stop relay attacks?
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A Faraday pouch (signal-blocking key case) can reduce relay attack risk when the key is stored at home. However, it does not protect against OBD key cloning or key theft. A CAN-bus immobiliser like IGLA provides a more robust, always-on defence.
What's the best defence against relay attack in Melbourne?
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An IGLA CAN-bus immobiliser is the most effective single countermeasure against relay attack. It requires a driver PIN before the engine starts, making a successful relay attack irrelevant — the car is unlocked but cannot be driven.
What we install.
Learn more.
IGLA is a CAN-bus PIN immobiliser that integrates into your vehicle's factory electronics and prevents the engine from starting without a driver-set PIN — even with a cloned or relayed key.
A CAN-bus immobiliser integrates directly into a vehicle's Controller Area Network to prevent engine start at the software level — unlike basic wire-cut immobilisers that can be bypassed by finding and bridging the cut wire.
OBD theft is a method where criminals use the vehicle's OBD-II diagnostic port to program a blank key to the car's ECU, allowing them to drive away with a fully functional duplicate key — often in under 5 minutes.