Keyless car theft: how the relay attack works

Published 9 July 2026

The principle: replaying your key from a distance

Your keyless fob constantly emits a short-range signal. When you approach, the car detects it and unlocks. The relay attack artificially extends that range: an accomplice stands near your home with a first device that picks up the signal from the key, sitting in the hallway or on the console. The device relays it to a second one, held next to the car. As far as the vehicle is concerned, the key is there: it unlocks and starts.

The operation takes less than a minute and leaves no trace of forced entry, which also complicates the insurance claim. Around three out of four keyless vehicles are vulnerable to this technique, and it has become one of the favourite methods of organised crime networks. Worldwide, Interpol estimates that illicit vehicle trafficking generates around USD 19 billion in criminal revenue each year.

The simple countermeasures (and their limits)

• A faraday pouch or box for the key: effective at home, provided you use it every time, holidays and visitors included.
• Switching off keyless entry at night, when the vehicle allows it: few drivers keep it up.
• A locked garage, lighting: deterrents, but experienced crews work around them.

These habits reduce the risk of the car being opened. They do nothing once the vehicle is gone. That is where the question changes in nature: it is no longer about preventing the theft, but about recovering the vehicle.

After the theft: the part we play

Professional thieves know it: an ordinary tracker goes silent under a GPS and GSM jammer. Our after-theft systems connected to an INCERT-approved monitoring station are built for exactly this scenario: jamming detection triggers an immediate response (alarm, starter cut-off or door locking, your choice), and localisation continues even outside internet coverage, including if the vehicle crosses the border.

For high-value vehicles, this is no longer optional anyway: most Belgian insurers require such a system above around EUR 60,000. Our guide to insurer requirements sets out the procedure.

In short

Keep the key in a faraday pouch: it is free and immediate. And if your vehicle is worth targeting, equip it to be found again: that has been our trade since 1993.