Most recent cars have an electronic key that lets the owner get into and start the car.

    The electronic key is called a "fob" to those who know about the technology. The fob sends a short-range signal to the car. As the owner gets close, the fob unlocks the door.

    But the new technology also makes it easier for criminals to open the car without the key.

    When you lock your car and take the key with you inside your home, the fob does not stop sending its signal.

    Thieves, who have special equipment known as scanners, will pass by streets with a lot of cars. If the scanner shows that a fob is sending a signal, the thieves use a device that clones the signal and opens the car doors.

    Government officials around the world have asked carmakers to warn car buyers of the risks of the new technology. They also have asked them to make the fobs more secure.

    Until then, what can you do to prevent your car from being stolen?

    Steve Launchbury has some suggestions he shared with the Associated Press. He is the head engineer of automotive security company Thatcham Research based in Britain.
    Steve Launchbury与美联社分享了一些建议。他是英国汽车安全公司Thatcham Research的首席工程师。

    Place your key in a protective bag

    "It's relatively easy for drivers to protect themselves," he said.

    The first tip is to put your key into a protective container or bag when you get home. One kind is called a Faraday bag. They are not very costly. The bag is made from a special metal material called mesh that blocks the signal from the fob. Just do not forget to put any extra keys you have into that bag, too.

    Some advice that is easy to find online says people should put their keys into the microwave or freezer to prevent their signal from being stolen. Launchbury said that does not work and it could harm your key.

    Get a steering wheel lock

    You may have seen large locks that go across the steering wheel in television advertisements many years ago. It turns out they are still useful. They may be considered "old school," but the presence of big locks that are easy to see makes car thieves turn away. The only problem is that you must take extra time to unlock the device and put it away before you can drive away.

    Change the settings

    Some car makers permit owners to deactivate the signal sent out by the fob. For Ford, Honda and Audi, owners can use their car's touchscreen system to find the correct way to turn off the signal. For Toyota, you can turn off the signal by pressing a combination of buttons on the fob.

    Read your car's owner's manual to be sure how to do this.

    Some car makers include motion sensors on their key fobs. If the fob has not been moved in a while, the fob turns off.

    If you buy a used car, some experts suggest that you get your keys reprogrammed in case the earlier owner still has a key.

    New theft techniques

    Launchbury said some cars have a new system called a controller area network, or CAN. The network permits different parts, or components of the car to communicate with each other. He said some thieves are trying to join the CAN through some physical electronic connection to unlock the car. They can do this by removing a headlight and plugging in a device that lets them in the car's network.

    The device can send a signal, such as "unlock" or "start" to the central system.

    Launchbury said this is where the physical lock can cause thieves to change their mind and force them to move on. Owners can also consider electronic immobilizers. These devices prevent a car from moving even if a thief gets into the internal system. However, immobilizers can be costly.

    I'm Dan Friedell.