Key fobs are handy targets for thieves

Your car is always listening for the electronic signal from your key fob. If it’s a newer model, you might not even have to press a button, just approach your car and the doors will unlock. In some cases, the engine will turn on.

The key fob’s signal is easy for thieves to intercept and might let them drive off in your car. The fob uses a computer chip to create a unique code that it sends to the car’s security system. The car has a chip that uses algorithms to generate a second code. If the codes match up, the car opens.

Each key fob/car security pair is unique, but researcher have found that by intercepting the signal twice, they could narrow down the possible combinations. After that a computer can figure out the code in just a half-hour and unlock the car.

USA Today‘s Kim Komando says always-on fobs present a serious weakness in your car’s security. As long as your keys are in range, anyone can open the car and the system will think it’s you. That’s why newer models won’t unlock until the key fob is within one foot.

Thieves, however, can buy an inexpensive signal amplifier over the Internet. That means your keys could be in the house, but a thief could walk up to the car and open it.

You can buy a signal-locking pouch to hold your keys. Or you can put the key fob in the refrigerator.

You can also just wrap the key fob in aluminum foil, but wrap it well so it can’t leak the signal.