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More car models get sleeping key fobs to combat keyless theft

Six new models rated as Superior in the latest batch of Consumer Security Ratings from Thatcham Research...

Keyless car theft
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Claire Evans
6 Nov 2019 07:40

In its third batch of security testing, independent automotive research centre Thatcham has revealed that six new car models are able to withstand attempts to break into them using scanner technology. 

The Audi A6 Allroad, BMW 1 Series, 8 Series and X6, Ford Puma and Volkswagen Passat all come with motion sensors in their key fobs (either as standard or as an optional extra) that detect when the key hasn’t moved for a set time and activate a sleep mode. 

This means the car’s keyless entry system is disabled because the key is no longer emitting the radio code that would usually automatically unlock the car’s doors when the owner stands next to it. The key starts to emit the code again as soon as it is moved.    

While the introduction of this technology is viewed as a positive step by Thatcham, it’s not the best solution to the problem of cars with keyless entry and start systems being more vulnerable to theft than those with conventional locks and ignition systems.

“The motion sensor fob is a good short-term option,” said Thatcham's chief technical officer Richard Billyeald, “but the goal for car makers must be to design out the vulnerability entirely. Until then, a fundamental security flaw remains.”

Billyeald also points out that car makers have chosen to select different lengths of time before the fob becomes inactive; in some cases it only needs to be still for 30 seconds, in others it takes as long as 30 minutes for the ‘sleeping’ mode to be activated. 

Those that take longer to activate are more vulnerable to relay attacks because thieves could follow someone home and then use scanner technology to grab the car’s code from outside the house once the owner has hung up the keys.  

Although sleeping key fobs make the latest models secure, there are many used cars with keyless entry systems that don’t have this technology and can’t be retrofitted with it. Owners of older cars are advised to improve the security of their cars by storing the keys in a blocking pouch or safe when they’re not being used.  

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How do keyless systems work?

Car security

A large number of new cars have keyless entry either as standard or as an optional extra, and there are thousands of second-hand vehicles already on the road with this technology.

To provide car owners with added convenience, keyless entry systems sense when the keys are close and unlock the car doors when the owner pulls on the door handle or touches a sensor on it. This means parents carrying children and drivers carrying large or bulky items don’t have to scrabble about in bags or pockets for keys. In fact, when coupled with a keyless start system, which enables the car to be started by pressing a button, without the need to put a key in the ignition, owners can permanently leave their car keys in a bag or pocket.

The key emits a code, or a series of codes, which are picked up by antennae in the car’s bodywork. However, this code can also be grabbed by a scanning device and sent to a booster unit that repeats it next to the car door to open it. Because the car thinks it’s the owner who wants access to it, the other security systems on the car, such as the alarm and engine immobiliser, aren’t activated when the car is unlocked.

If the car has a keyless starting system, this same booster can also be used while pressing the start button to fire up the engine and drive the car away. This is seen as a second level of vulnerability by security experts, because thieves can get a car to start without having to damage it and don’t need the physical strength to break an ignition lock. 


Next: What Car? security test 2019 >>

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