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Relay Crime: Keyless Car Entry Theft

car relay crime prevention

Keyless car entry is a luxury that is found with many modern vehicles but it is a feature that is putting you at risk from relay crime. Car criminals are now using state of the art computers to hack into the cars computer/ecu, which allows them to start the vehicle and drive away in minutes. These devices that they are using can be found online and can be bought for very little, which is very worrying for us motorists.

However, it is not just vehicles that have keyless entry that are at risk. If your car has the ability to access the internet such as maps, it is also at risk of relay crime.

There are various methods of preventing relay crime with products such as a car key signal blocking pouch that prevents any signals being transmitted. However, the majority of people are turning to “old-school” tactics to act as a deterrent to criminals.

How Does a Relay Attack Work?

Rewind 30 years ago and the main method of stealing cars was to hot wire it but you would still need to break into the car. A relay attack is the latest method that is far more simpler for the criminal and you do not need to force any entry to gain access.

Keyless car entry theft is on the rise with many criminals understanding the process and seeing how easy it is to do. In order for it to work, there needs to be two criminals and they must have a powerful transmitter, which can be purchased online of course!

Below is a simplified version of events to how a relay attack happens.

  1. Criminal #1 firstly uses the transmitter to ping the cars locking system to impersonate the key.
  2. After trial and error, the locking system will then respond and send a signal that the key is meant to pick up and respond to.
  3. Criminal #1 then forwards the transmitting signal to criminal #2 who will be located near the house.
  4. Criminal #2 uses his transmitter to send it on to the key fob where the relay sends back the correct response. This is then forwarded back to criminal #1’s transmitter and they will have full access of the locking system and ignition.

The graphic below explains the process far easier and it truly is this simple.

relay crime infographic

How to Prevent Keyless Car Theft

Car manufacturers are doing their best with plenty of research and development to help tackle the problem. Many manufacturers now have new key fobs that do not transmit the signal that the criminals require for this relay crime.

However, will this result in the keyless entry not working? With these new key fobs, the keyless functionality will only work when the key fob is moving. For example, if you are walking towards your car, the key fob will transmit the signal. Therefore, when you are asleep and the key fob is on the side, there will be no movement and no signal being transmitted for the criminals to use.

However, what about the other car owners that have a key fob that transmit a signal all the time? One of the easiest solutions is by using a car key fob case that prevents the keys signal from being transmitted further than the case. An example of this is the The Faraday Cage Key Signal Blocker below, which is the best way to prevent keyless entry theft of your vehicle and is much cheaper than you expect.

Be sure to have a key signal blocker for each key fob that is in your house. Some people may the mistake of only using the bag on their main key that they keep in the house. However, thieves may be able to get the signal they need from the spare key that may or may not be hidden elsewhere.

Below is my personal key fob signal blocker that I use for an Audi RS6 that uses keyless entry and it fits into the bag with plenty of room spare for other keys.

Relay Crime

Alternatively, using old school tactics work just as well as they did back in the day to prevent keyless car theft and these include an anti theft steering wheel lock, locking the car in place with a wheel clamp boot and even a secondary car alarm system. Many car owners will even go a step further and invest into a GPS tracking system for cars to help locate the car if it get stolen.

If a car criminal came across these old school tactics, they are more than likely going to target a more easier option. They are an efficient deterrent and work well but adding such anti theft devices such as a steering wheel lock or clamp involves a lot of effort every time you drive your car. However, it is the best way to prevent keyless entry theft and if there is a spike of such crime in your area, it is highly advised.

Relay Crime Conclusion

Unfortunately, car theft will always be a thing but manufacturers are trying their best to prevent it in ways of software updates and vehicle recalls.

Police are also “upping” their game and fighting against the sale of relay crime devices and seizing any they find.

If there is a sudden increase of relay crime in your area, invest into a signal blocking pouch or an old school locking device for peace of mind.

procarreviews author

Written By Dan

About the Author

Dan is an automotive journalist and owner of over 10 cars ranging from supercars, tuned cars, classics and your good old beater cars. He always likes to get his hands dirty with nut and bolt restorations or detailing sessions using the best products on the market.

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