Relay Attack Protection: A Complete Guide

What Is a Relay Attack?

A relay attack is a high-tech theft method that targets vehicles with keyless entry and push-button start. Thieves use portable relay devices to capture and extend the signal from your key fob — even if it's inside your house — tricking your car into thinking the key is right next to it.

The result? Your car unlocks and starts in seconds, with no broken windows, no forced entry, and no alarm. By the time you realise what's happened, your vehicle is miles away.

Relay attacks have become the dominant method of vehicle theft across the UK, including Leeds, Bradford, Wakefield, Harrogate and throughout Yorkshire.

How a Relay Attack Works — Step by Step

1. Thief 1 stands near your home (usually outside the front door or bedroom window) with a relay device that scans for your key fob's signal
2. The device captures the signal and transmits it to Thief 2, who is standing next to your car with a second relay device
3. Thief 2's device relays the key's signal to the car — the car recognises it and unlocks
4. Thief 2 presses the start button — the engine starts because the car believes the key is present
5. Both thieves drive away — total time: under 60 seconds

No noise. No damage. No alarm.

Which Vehicles Are at Risk?

Any vehicle with keyless entry and push-to-start is vulnerable. This includes most vehicles manufactured from around 2010 onwards, particularly:

• BMW — 1, 2, 3, 4, 5, 7 Series, X-Series SUVs
• Audi — A1–A8, Q-Series SUVs, S/RS models
• Mercedes-Benz — A, C, E, S Class, GLC, GLE
• Land Rover — Range Rover, Range Rover Sport, Velar, Discovery, Defender
• Volkswagen — Golf, Tiguan, Touareg, Arteon
• Ford — Focus, Fiesta (ST models especially)
• Tesla — Model 3, Model Y, Model S
• Porsche — Macan, Cayenne, 911, Taycan

If your car unlocks when you walk up to it with the key in your pocket, it is at risk.

Why Factory Security Fails

Your car's factory immobiliser is designed to prevent hot-wiring — it checks for the key's transponder signal before allowing the engine to start. But in a relay attack, the car genuinely receives the key's signal (relayed from inside your house). The factory immobiliser is satisfied. The alarm doesn't trigger. The engine starts.

This is why factory security is fundamentally unable to prevent relay attacks — the system is working correctly, it's just being deceived.

The Solution: A CAN PHANTOM Immobiliser

A CAN PHANTOM immobiliser solves this problem by adding an independent layer of security that doesn't rely on the key fob at all.

How CAN PHANTOM Stops Relay Attacks

• Independent PIN code — the engine cannot start until a unique PIN sequence is entered using your vehicle's existing buttons (volume, steering wheel, climate controls)
• No key fob involved — the PIN is entirely separate from the keyless system, so relaying the key signal is useless
• Covert installation — there are no visible components, no extra fobs, no LED lights to indicate the system exists
• No bypass — the immobiliser is integrated into the CAN bus network; it cannot be hot-wired or bypassed

Even if thieves successfully relay your key and start the car, the engine will cut out within moments because the CAN PHANTOM PIN hasn't been entered. The vehicle is going nowhere.

An Alternative Immobiliser: Scorpion X-Series

The Scorpion X-Series immobiliser is another excellent option for relay attack defence. Like the CAN PHANTOM, it integrates directly into your vehicle's CAN bus and prevents the engine from starting without authorisation.

Scorpion X-Series Key Features

• Stealth installation — no visible components, no LED, no PIN pad
• CAN bus integration — cannot be hot-wired or bypassed
• Thatcham insurance recognised — may reduce your insurance premium
• No monthly subscription — one-time installation cost
• Pairs with Scorpion GPS trackers — combine with an S5 or S7 tracker for the ultimate layered defence

Both the CAN PHANTOM and Scorpion X-Series provide robust protection against relay attacks. As an approved installer for both products, Bailey's Auto Solutions can help you choose the right system for your vehicle and budget.

Additional Layers of Protection

GPS Tracker

A Scorpion GPS tracker adds recovery capability. If your vehicle is somehow moved without authorisation, you receive instant alerts and can track its location in real time via smartphone app.

Faraday Pouches

A Faraday pouch blocks your key fob's signal when not in use. This prevents the initial signal capture but is not foolproof — thieves can still scan when you're walking to the car. Use as a supplementary measure, not your primary defence.

Steering Wheel Lock

A physical steering wheel lock is a visible deterrent. While it can be defeated, it adds time and noise — many thieves will simply move on to an easier target.

Don't Become a Statistic

Vehicle theft via relay attack is increasing across Yorkshire. Recovery rates are low, and the emotional and financial impact is significant. A CAN PHANTOM immobiliser fitted by Bailey's Auto Solutions — approved installers serving Leeds and the wider Yorkshire area — takes just 2–4 hours and provides lifetime protection.

Call 07387 719207 or enquire online for a free quote. We come to you at home or work.