How Criminals Hack Keyless Entry Cars (And How to Fight Back)

1. What Is Keyless Car Theft?

Keyless car theft - also known as a relay attack - targets cars with keyless entry and push-start systems.

Here’s how it works -
Your key fob constantly emits a short-range radio signal to tell your car it’s nearby. Thieves use a relay amplifier and relay transmitter to extend that signal - one thief stands near your house or pocket to capture your fob’s signal, while the other stands by your car.

The car then thinks the key is right next to it - unlocks - and starts. All of this can happen in under 30 seconds.

2. The Scale of the Problem in the UK

Keyless theft isn’t just a London issue - it’s happening across the country.

According to Home Office data, more than 48,000 cars were stolen in 2024 in England and Wales, and over half were believed to involve keyless entry systems.

The most commonly targeted cars include:

Car thieves now use tech that can be bought online for under £100. The devices are often disguised as diagnostic tools or “signal boosters”, making them hard to detect.

3. How Keyless Car Hacking Works

Let’s break down the most common methods criminals use to steal keyless cars in the UK.

Relay Attack

This is the most widespread method. The thieves use two small devices - one close to your key fob (like outside your front door), and one near the car.

• The first device captures the key signal.

• The second transmits it to the car.

• The car unlocks - starts - and drives off.

All without breaking glass or setting off alarms.

Signal Jamming

Criminals block the lock signal when you press your key fob. You think you’ve locked the car - but it’s actually open.

• They use cheap jamming devices that stop the signal reaching your car.

• You walk away - and they simply open the door.

Key Cloning

This involves copying the signal data from your key fob using specialised tech. It’s often used during servicing scams or valet parking situations if criminals get brief access to your key.

CAN Bus Hacking

A newer and more advanced method. Thieves access the wiring behind your headlights or bumper and send fake electronic messages directly to the car’s control unit.
The system thinks the key is nearby and unlocks the car - completely bypassing keyless entry systems.

4. Why Keyless Cars Are Easier Targets

Car manufacturers have focused on convenience - but in doing so, they’ve introduced new vulnerabilities.

Here’s why keyless systems make theft easier -

• Keys constantly emit a signal that can be intercepted.

• Many cars don’t time-limit the signal, so the system stays active even when you’re far away.

• Some older keyless systems lack encryption or use outdated software.

• Criminals can easily find tutorials and cheap equipment online.

It’s a modern problem that even luxury car brands haven’t solved yet.

5. How to Protect Your Keyless Car

You don’t have to give up convenience to stay safe. With a few smart habits and tools, you can make your car far harder to steal.

1. Use a Signal-Blocking Pouch (Faraday Bag)

A Faraday pouch blocks your key fob signal completely when not in use.

• Always store your keys inside one overnight.

• Don’t forget the spare key - it’s just as vulnerable.
  You can buy a good one for under £10 - a small investment to stop a big loss.

2. Turn Off Keyless Entry (If Possible)

Some cars let you disable keyless entry through the onboard settings. Check your car’s manual or contact the dealer. It’s one of the simplest fixes if you don’t need constant keyless access.

3. Use a Steering Wheel Lock

It might look old-school - but it works. A physical steering lock adds a visible deterrent and slows thieves down. Criminals prefer easy targets - so make your car look like hard work.

4. Install a Tracker

If your car is stolen, a GPS tracker can help police locate it quickly. Many insurers now offer discounts if you install one.

Choose one with real-time tracking and movement alerts for extra peace of mind.

5. Check for Firmware Updates

Manufacturers sometimes release software patches to fix keyless vulnerabilities. Ask your dealer to update your car’s firmware during servicing.

6. Be Smart About Where You Park

At home - park your car in a locked garage if you can. If you have to park outside, keep keys far from doors or windows - ideally in a Faraday pouch or metal container.
In public - park under CCTV or in well-lit areas.

6. The Role of Car History Checks in Preventing Keyless Fraud

Here’s something many drivers don’t realise - keyless theft can affect the car’s history record.

When stolen cars are recovered, they often get cloned identities or false VINs before being sold. Running a car history check through TopCarCheck.co.uk helps you spot these warning signs before buying.

A vehicle check will show:

• If the car was ever reported stolen

• Any VIN mismatches

• Mileage discrepancies

• Insurance write-off records

• Outstanding finance or theft alerts

It’s one of the few ways to make sure the “bargain” used car you’re eyeing isn’t a stolen clone.

7. What the Police Say

The National Vehicle Crime Intelligence Service (NaVCIS) and local police forces have repeatedly warned that keyless thefts are on the rise.

They recommend:

• Always double-check your car is locked (look for mirrors folding or indicators flashing)

• Use physical security like steering locks

• Store keys in Faraday pouches

• Report suspicious activity near driveways

Law enforcement is catching up, but technology moves fast - meaning prevention is still your best defence.

8. The Hidden Cost of Keyless Theft

Even if your car is insured, getting it stolen can cost you more than you think.

Once a car is stolen using a keyless attack, recovery rates drop sharply - especially if the vehicle is exported or broken up within hours.

That’s why prevention is far cheaper than cure.

9. Future of Keyless Security

Manufacturers are aware of the issue and are introducing new layers of protection -

• Motion sensors inside key fobs (turn off signal when not moving)

• Ultra-wideband (UWB) tech for precise location detection

• Encrypted communication between keys and vehicles

These updates are slowly being rolled out in newer models. Until then, combining digital and physical security remains the best approach.

10. Final Thoughts - Stay Smart, Stay Secure

Keyless cars are convenient - but convenience comes with risks.

Criminals no longer need crowbars - just clever tech. But with a few smart moves, you can stop them in their tracks.

Use Faraday pouches - fit steering locks - install a tracker - and most importantly, check your car’s background before you buy.

A quick car history check on TopCarCheck.co.uk can uncover whether a used car was previously stolen, written off, or cloned - helping you avoid costly mistakes and keep your investment safe.

Tech evolves fast - but so do smart drivers. Stay one step ahead.