Car Theft Group Test - Britain's Most Secure Cars

With car theft an ongoing problem, we tested seven car security systems to find out how easy it is to get into them and drive away without consent...

Car security

To find out how vulnerable keyless entry and start systems make cars to theft, we asked two security experts – Ron Cliff and Voskan Pehlivanjan from Edilock – to use any non-damaging technology to gain access to seven cars with keyless entry.

In five instances, our fake thieves used a form of entry that’s often referred to as a relay attack. It involves two electronic devices – one to pick up the signal from the key fob and a booster unit that repeats the code next to the car door to open it. On two of the cars, they used a lock-picking device to unlock the doors.

We measured the time it took them to gain entry to each car and the time to start the engine, and combined these two to give us a total theft time so we could compare them.

In general, keyless entry fobs have a range of five to six metres, so one of the scanner units has to be no farther than this from the fob. The distance between the two scanners can be up to 50 metres, though, so don’t think that your car is safe just because the keys are a fair distance from it; if a thief can get close to the fob, the car is vulnerable.

Our tests revealed that it can be 90% faster to steal a keyless entry car than a car with old-fashioned locks and ignition – in as little as 10 seconds. That compares with the two and a half minutes the security experts said it would take them to get into a car without keyless entry.

When the additional security features were working on all relevant cars, they were able to drive off in two of the seven cars in 60 seconds or less.

When the extra security measures weren’t working, they could steal six out of the seven cars in this time. The only car they couldn’t start was the Land Rover Discovery, which has ultra-wide-band radio technology.

Audi TT RS Roadster - not stolen

Advanced Key inactive: Get into car Not possible Drive away Not possible

Advanced Key active: Get into car 5sec Drive away 5sec

Car security

The TT RS Roadster doesn’t come with keyless entry as standard; without it, it’s harder to get into than when it’s specced with the £1495 Comfort and Sound Pack, which includes the Advanced Key keyless entry system. The optional fob has a motion sensor, but it can’t be put to sleep immediately and doesn’t cut in until the fob has been motionless for 15 minutes. We believe this would prevent thieves from taking the car from a driveway at night. However, with the key fob awake, our fake thieves could drive away in the TT in just 10 seconds.

In response, Audi’s parent company, the VW Group, said: “We are continually working on improving our security measures in order to hinder or prevent such manipulation. We closely observe how thieves work and discuss this topic with police authorities and insurers.”

Read our review of the Audi TT RS, or see the best deals on a TT  

BMW X3 xDrive20i M Sport (2018 model) - not stolen

Digital smart key inactive: Get into car Not possible Drive away Not possible

Digital smart key active: Get into car 40sec Drive away 20sec 

Car security

BMW declined to provide us with a car for our test, so we sourced one elsewhere. Our X3 has a digital smart key with motion sensor technology – part of a Technology Pack that’s standard with Sport trim. BMW told us that the Comfort Access system on the smart key has a “security system that automatically cuts off the signal emitted from the key when it has been stationary for a set amount of time”.

We believe this is two minutes; the key cannot be activated immediately. However, when the motion sensor technology hasn't cut the signal the key's code can still be picked up and we were able to steal the X3 in 60 seconds. When the motion sensor technology is working, this would prevent the car from being stolen.

A spokesman also said all new BMW and Mini keyless entry keys now have motion sensor technology as standard. “Every single case we are aware of where a relay attack method has been used is when the key is left unattended and not in a pocket – hence our approach to the solution.” He added that owners of many older BMW models can pay to have the motion sensor technology retrofitted; the price of this differs between models.

Read our review of the BMW X3, or see the best deals on an X3 

DS 3 Crossback Puretech 155 Ultra Prestige - stolen in 10sec

Get into car 5sec Drive away 5sec

Car security

The range-topping DS 3 Crossback Ultra Prestige trim level comes with keyless entry as standard. The car’s flush-fitting door handles popped out to give our thieves access after just five seconds. It was also easy for them to repeat the code to start the engine using the push-button starter.

The PSA Group, the parent company of DS, responded by saying: “PSA Group has created a dedicated division to analyse and treat potential or proven weaknesses of vehicle security, including to monitor statistics and internet activity. PSA Group works closely with the police and regulatory authorities in order to analyse theft methods.” It also said the keyless entry systems on the latest cars could be deactivated by dealers if owners were concerned.