A few months ago, I bought a new used car, trading in my beloved 20-year-old Highlander. When I got behind the wheel of my new 3-year-old Rav4 I asked the sales associate, “Where is the key?” She pointed to a button and told me that all I needed to do was push it and the car would start. As long as the key fob was in the car. It’s called keyless entry.

Welcome to the space age, I thought, flashing back to my driving test in my family’s manual transmission wind-up window Ford Custom 500.

What I didn’t realize when I pulled out of the car lot with my shiny new toy is that these keyless cars not only are convenient to the driver, they are also very convenient for car thieves.

Car theft is surging

In 2023 more than one million vehicles were reported stolen in the US according to the National Insurance Crime Bureau.  California accounted for the highest number of vehicle thefts nationwide in 2023 with 208,668 vehicles reported stolen. The District of Columbia had the highest theft rate. 33,596 cars were stolen in the New York metro area alone. One of the reasons is all of the new technology—such as keyless entry.

“Criminals are employing increasingly sophisticated methods to steal vehicles, including the use of advanced technology to bypass security systems,” said David J. Glawe, President and CEO of NICB. “From keyless entry hacks to relay attacks on key fobs, perpetrators are exploiting vulnerabilities in modern vehicle security measures with alarming success rates.”

How does car theft by key fob work?

You think, “My car is safe. They key is on the kitchen counter.” Think again. Your key fob continues to communicate with your car’s electronic system even when you walk away or put it on the hook by the door in your home.

Relay attacks

Thieves often steal cars by exploiting vulnerabilities in keyless entry systems through a method known as a relay attack. This technique involves the following steps:

• Signal Interception: Thieves use a device to capture the radio signal emitted by a key fob. This signal is typically intercepted when the fob is within close proximity to the car, such as when it is left near doors or windows inside a house. It’s also possible to intercept the signal if you are carrying the fob in your pocket or purse.
• Signal Amplification: Once the signal is captured, it is amplified and relayed to another device held by an accomplice near the car. This tricks the car into thinking the key fob is nearby, allowing the thieves to unlock and start the vehicle without physically possessing the key. Thieves then can drive away.
• Clone the Key: Thieves essentially clone the key fob’s signal, enabling them to repeatedly start the car until the signal is deactivated or the car is recovered.

Reprogramming

Another method thieves use is with a reprogrammer to steal a locked car. This method involves using a key fob programming tool, which can be purchased online, to reprogram a blank key fob. Here’s how it typically works:

• Break in. Thieves gain access to the car’s onboard diagnostic (OBD) port either by breaking in (breaking a window), jamming keyless entry signals, or by targeting specific weak points in a car’s security system.
• Access the car’s electronic system. Once they get into the OBD they use a legal, commercially available OBD programming device that are easily purchased online. This tool allows for communication with the car’s electronic systems. It’s typically used by mechanics for diagnostics and maintenance.
• Reprogram the key fob. Using the programming tool, they delete existing keys and program a new blank key fob to match the car’s system. This effectively creates a new key that can unlock and start the vehicle–and the fob you have will no longer work.

The entire process can be done quickly, often in a matter of minutes, allowing thieves to drive away with the car without needing the original key fob.

To protect against such thefts, use additional security measures like steering wheel locks and be cautious about the security of the vehicle’s OBD port.

How to protect your car

There are several effective countermeasures available to mitigate this risk.

Don’t leave the fob in your car

This may seem obvious, but in the majority of stolen keyless car cases the owner left the keys in the car. It’s easy to forget to take your key fob with you because you’re not manually turning off the car with a key. The fob could be sitting on the console, or on the seat, unseen.

Store the fob at a distance from the car

When at home, store the fob as far away as possible from the car and away from glass doors and windows. Use a metal container or safe for secure storage for your keys.

Signal-blocking technology: Faraday pouch or box

Faraday containers block electromagnetic signals, thereby preventing unauthorized interception of the key fob’s signal. The technology was invented by English scientist Michael Faraday in 1836.  According to Inshur.com, utilizing a Faraday bag is a highly recommended protective measure.

Faraday products are widely available at various price points. You can choose either a box, for a place in your home, e.g., or a pouch, which can be used to store the fob at home or carried with you. (It also preserves the life of your fob battery.)

briidea Faraday Box Key Fob Protector

The briidea car theft prevention box is lined with a high-quality material that stops any signal leaving the box and lets you store multiple keys in one place. $14.99 on Amazon.

TICONN Faraday Box, Car Key Fob Protector

The larger TICONN Faraday box blocks car key signals, cell phones, contactless credit cards and more. $19.95 on Amazon.

Lanpard Faraday Bag for Key Fob

The Lanpard faraday bag is made of premium carbon fiber material and double military-grade RF shielding cloth, is waterproof, and can block WiFi (2.4 and 5 GHz), Bluetooth, GPS, RFID, car key signals, etc.  $13.99 for a 2-pack on Amazon.

DIY method

For a temporary solution, AutoInsurance.com suggests encasing the key fob in multiple layers of aluminum foil. While not as sophisticated as a Faraday bag, this method can provide a quick, makeshift barrier against signal interception.

When you are out and about

In public spaces, particularly parking areas, maintain vigilance and, when possible, avoid using the remote locking function. Car thieves stalk these areas; as soon as you walk away (with the fob in your hand or bag) they can begin the signal interception process, which takes only minutes.

Lock the car when you are standing next to the car. Then put the fob in a Faraday pouch i your bag or pocket. Heightened awareness can significantly reduce vulnerability to potential threats.

Turn off your key fob

Does your fob have an option to deactivate its wireless signal when not in use? Check with your car dealer to learn how to do it.

If you suspect your key fob may have been compromised, the best course is to have it reprogrammed by an authorized dealership or professional locksmith.

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