Faraday Box For Car Keys – How To Keep Your Keyless Car Safe

Here’s how and why to use a faraday box to prevent your keyless car from being stolen by cunning would-be car thieves in seconds.

Mark Watson, smartsafehome

Keyless cars are great, and it’s a convenient feature that many car lovers find useful. Unfortunately, one of the big drawbacks of keyless entry cars is that owners can have their car stolen by thieves in mere seconds.

Did you know that 94% of vehicles in the UK are reportedly stolen without using the key?

Luckily, there is a cheap and easy way of mitigating the risk of getting your prized possession stolen from your driveway in the middle of the night. Do yourself a favour and get a Faraday Box. Faraday boxes are small boxes that block the signal emitted from the transceiver in your car’s keyfob.

This prevents car thieves from being able to use a signal amplifier to open the car, as this method, known as “relay theft”, requires the criminal to be able to read the signal in the first place.

What Is Relay Theft And How Does It Work?

Relay Theft is a simple car theft method. Since keyless car systems work by recognising the short range radio waves emitted from the key, a relay attack is simply where a thief (or typically two thieves) amplify the radio signal from the key with a signal amplifier. Then, using a signal transmitter to pick up the signal, they impersonate the real key, get in and drive off. The crux of this operation is for the criminals to actually pick the signal up from inside of your house in the first place.

Since us humans are predictable, and there’s a very high chance that our keys are either hung next to the front door or in a bowl in the kitchen, it doesn’t take a genius to figure out where to point the amplifier. If the signal from the keys of your keyless ignition car are picked up, your car can be on the motorway in minutes, without breaking into your home at all.

This is what a faraday box prevents. By blocking the signal from the key from leaving the box, it makes relay theft (in theory) impossible.

How Does A Faraday Box Prevent Relay Theft?

The idea behind a faraday box or pouch is exactly the same as the more commonly known faraday cage. It’s an enclosure specifically designed to block signals entering or leaving the inside of the space.

Typically faraday boxes are constructed using some kind of metal lining, but the specific materials depend on the manufacturer.

There are a wide range of different options on the market, such as this faraday pouch which is more easily concealable than a larger box. Whether it’s a box or a pouch, they work in the same way.

How Do I Make Sure My Faraday Box Works?

Luckily, you needn’t worry about figuring out whether the faraday box you have just bought is safe. Testing if your car key is protected is as simple as approaching the car (with the key still in the box) and trying to open the car door.

If the car door remains locked when the key is next to it, then you’ve successfully made it a whole lot harder for would-be thieves to steal your car. Manufacturers use different technologies and wavelengths for their keys, so it’s definitely worth giving this test a try just to double check that your key really is protected from a possible relay theft.

Are There Any Free Alternatives To A Faraday Box?

I cannot recommend this for obvious reasons, but some UK car forum users have allegedly been keeping their keys in the microwave in an attempt to create a sort of makeshift faraday box. I would personally advise against this, because it’s all to easy to forget the keys are in there, and simultaneously destroy both your keys and the microwave in the process. On the positive side, your key probably won’t be emitting a signal once it’s been nuked for 5 minutes next to a lasagne!

I’ll put it this way. For the sake of forking out about £10-20, I think just getting a faraday box is the safer option. With the state of England today, you can barely get a pint in London for that, and I wish I was joking…

Do Faraday Boxes Work For Other Devices?

The short answer is yes. Not necessarily everything, but these boxes are sold as a means of protecting contactless cards and devices with bluetooth connectivity, so just about anything which makes use of wireless signals can be blocked if you get a good one.

Which Is Better, A Faraday Pouch Or Box?

This depends on your lifestyle really. If you work in a busy area and are concerned about your car being stolen in plain sight as you walk up to it (yes, it really does happen), then keeping your keys in a faraday pouch such as this one at all times is a good idea.

Many cars with keyless entry systems unlock even when you are a good distance away, which gives criminals just enough time to start the engine and run off with your beloved vehicle. A very slight potential downside with relying on a pouch is that over time, the materials may degrade from wear and tear over the years making the seal less effective.

On the other hand, a faraday box is considerably less portable than their smaller pouch alternatives, but a well constructed one is likely to last longer, with the benefit of being big enough to store multiple sets of keys and other items in there too.

If, for instance, you and your partner both own newer cars and have a handful of contactless debit/credit cards in your wallets, then investing in a more spacious box to keep everything in probably makes more sense than having to keep everything in a handful of different pouches.

Are Faraday Pouches Recommended By Authorities?

As a matter of fact, yes. In this archived post by Hertfordshire police, Inspector Nicola Dean said:

“You should also get into the habit of storing your fob as far away from your vehicle as possible when at home. Placing keyless fobs in a metal box or faraday pouch will make your vehicle even safer.”

Nicola Dean, Herts.police.uk

Additionally, Kia have even started selling their own branded signal blocking pouches as an option with car purchases (source).

This move by Kia was one specifically orchestrated by Kia UK, which highlights the gravity of the situation. Multinational car manufacturers are happy to continue making cars with keyless entry because this typically isn’t a problem in most of their markets, but the UK has become notorious for this new kind of crime.

Conclusion

Relay Theft is here to stay, and so is keyless car technology. It can be hard to avoid buying a car with this feature, especially in the luxury segment of the market, so the best option is to make a good effort to block your key’s signal and make yourself less of a target. Criminals go for easy victories, and if they need to break and enter to steal your key, they are much more likely to instead look elsewhere.

I hope this buyer’s guide on signal blocking devices for protecting your car has been informative. If you have any questions regarding home, internet or car security, please leave a comment and I’ll get back to you as soon as I can.

Stay safe!

Editor’s note: smartsafehome may receive a commission from some or all of the linked products in this post. We are not paid to recommend a specific product, and the recommendations are unbiased.