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Keeping your keyless car safe

Keeping your keyless car safe


Around one percent of the 32 million cars on our roads are fitted with keyless entry/start and criminals are taking advantage of a weakness in their security. with what's known as 'relay theft'.

Around one percent of the 32 million cars on our roads are fitted with keyless entry/start and criminals are taking advantage of the weakness in their security.

If your car is one of the thousands with a fob which lets you open the doors while you’re still several feet away and has a push stop/start button instead of a key, then you’re vulnerable to the rapidly growing threat of relay theft.

Relay theft is frighteningly easy, all theieves need is to buy a relay amplifier and a relay transmitter online, then use them to `capture’ the signal between the key fob and the car and boost that signal allowing them to get in, start and drive off. It can take no more than 20 seconds…

Having an expensive car is no guarantee of protection; search the internet and you’ll see CCTV footage of high-end cars being stolen in this way. Home Office figures show that car theft has doubled since 2014 and insurance payments for meeting claims caused by this increased by more than 20% in the January-March period this year against the same period in 2018. According to the Association of British Insurers, around £1.2 million a day was paid out meeting car theft claims, with one every eight minutes.

However, owners are not completely helpless and there are some very low-tech defence measures you can use to complement those the industry is offering.

One is the tin-foil trick. Wrapping the key fob in tin foil will go a long way to stopping the electronic signals, so the relay transmitter cannot pick them up. Tin foil will work up to a point, but it isn’t really designed for this and if you want better protection you can go a step further and buy a Faraday bag, named after the famous Victorian era scientist, Michael Faraday, who worked with electromagnetism.

Set of car keys on table with documents

Faraday bags are little pouches lined with a metallic material that blocks any wireless signals and are a great way of reducing your vulnerability to relay theft. You can get one for less than a tenner and given what that might save on your next insurance premium if you’ve made a claim for theft, then it should be considered a good investment.

You can test one by dropping your key in, walking several paces from the car and seeing if you can unlock the doors. If you can, then the bag isn’t working properly.

Some keys fobs can be turned off, usually by pressing a combination of the buttons on them in the right sequence, and you can find more details of this either in your owner’s handbook or by calling the dealer who will be able to assist.

At the most basic level, keeping the keys as far away from your home’s walls, windows or doors or even adapting the principle of the Faraday bag and dropping them in a lidded metal tin will also help.

Car makers are responding to the issue and some have developed key fobs with accelerometers in them which detect when the key is in motion, such as when the owner is walking towards or from the car or the vehicle is being driven, and will disable it when it isn’t. Effectively, the key goes to sleep.

The unpleasant fact remains though that more cars are vulnerable to this crime and in a recent initiative, Thatcham Research, which carries out research and testing for safety and security and works closely with the insurance industry, has devised the New Vehicle Security Assessment (NVSA). Its findings will affect cars’ insurance group ratings.

In the first publicised report, where 11 new cars were assessed earlier this year, five were ranked as having `poor’ levels of security because their keyless entry/ignition made them easy targets, but without that their grades would have gone up to `good’.

Richard Billyeald, Chief Technical Officer at Thatcham Research, said: “This initiative focuses on addressing keyless entry/start vulnerability. We’ve seen too many examples of cars being stolen in seconds from driveways.

“Security has come a long way since vehicle crime peaked in the early 1990s. But the layers of security added over the years count for nothing when they can be circumvented instantly by criminals using digital devices. The shame is that most of the cars rated ‘Poor’ would have achieved at least a ‘Good’ rating had their keyless entry/start systems not been susceptible to the Relay Attack.”

2019 model security ratings for relay theft resistance:


  • Ford Mondeo
  • Hyundai Nexo
  • Kia ProCeed
  • Lexus UX
  • Toyota Corolla Hybrid


  • Audi e-tron
  • Jaguar XE
  • Range Rover Evoque
  • Mercedes B Class
  • Porsche Macan

Silver Range Rover Evoque in countryside with beautiful sky

Richard added: “Our guidance for worried drivers is first and foremost to understand if your vehicle has a keyless entry/start system or not, as it’s often an optional extra. If it does, check whether there are solutions available with your key fob – can it be turned off overnight or does it go to sleep when not being used?

“Faraday shielding pouches can be effective, but test them first to make sure they do block the signal. Many are designed for credit cards so make sure they still close fully with a set of keys inside, to ensure maximum effectiveness.

“Storing all sets of keys, spares included, away from household entry points is also important as it hampers the criminal’s ability to relay the signal.

“And finally, it may in some cases be possible to turn the system off entirely, so it’s worth checking with your dealer.”

Follow these steps and you can help reduce the opportunity for thieves to take your car using relay theft.