Keyless entry systems offer convenience, but they’ve also introduced a new vulnerability: relay attacks. Car thieves are now using sophisticated techniques to exploit these systems, making it easier than ever to steal vehicles without physical keys. If you own a car with keyless entry, understanding How To Block Key Fob Signals is no longer optional—it’s a crucial step in safeguarding your property.
This guide will provide you with a comprehensive overview of key fob signal blocking methods, from simple DIY solutions to more advanced and reliable options. We’ll explore the effectiveness of each approach, helping you make an informed decision to protect your vehicle from modern theft techniques.
Understanding Keyless Car Theft and Why You Need Signal Blocking
The rise of keyless entry and start systems has unfortunately coincided with a surge in car thefts that don’t require hot-wiring or forced entry. These modern methods target the radio signals transmitted between your key fob and your car.
Who is at Risk of Keyless Car Theft?
If your car uses a key fob to unlock and start without physically inserting a key, your vehicle is potentially vulnerable. It’s a common misconception that only luxury or high-value cars are targeted. In reality, any car with a keyless system can be a target, and thieves often operate opportunistically. There are no specific criteria that make you immune; enhancing your car’s security is a proactive measure every keyless car owner should consider.
While some car manufacturers are implementing better security measures, research indicates that vulnerabilities still exist across various makes and models. Organizations like Thatcham Research have conducted studies highlighting the varying levels of security in keyless systems. Their findings emphasize that while progress is being made, consistent and robust protection across all brands is still lacking. Richard Billyeald, Chief Technical Officer at Thatcham Research, points out that while some manufacturers are incorporating relay attack countermeasures, a universal solution is needed for all keyless systems.
Certain car models have shown better resistance to relay attacks due to features like motion sensor technology in their key fobs. However, experts caution that these are often short-term fixes, not foolproof solutions against determined criminals.
How Thieves Steal Keyless Cars: Common Techniques
Understanding the methods thieves use is the first step in learning how to block key fob signal effectively. Here are some prevalent techniques:
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Relay Attacks: This is perhaps the most widely discussed method. It involves two thieves using signal-amplifying devices. One thief positions themselves near your house or wherever you keep your keys, while the other is near your car. The device near your keys captures and amplifies the fob’s signal, “relaying” it to the device near the car. This fools the car into thinking the key is nearby, allowing the thieves to unlock and drive away. This technique highlights why blocking car key fob signal at home is critical.
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Jamming: Thieves use electronic jamming devices to block the locking signal from your key fob when you try to lock your car. You might walk away thinking your car is secure, but it remains unlocked, leaving it vulnerable to theft.
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Programming: Modern cars often have onboard diagnostic ports (OBD). Thieves can access these ports, plug in their devices, and program a blank key to start your vehicle, bypassing the need for your original fob altogether.
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App Hacking: With the increasing connectivity of cars, some have smartphone apps for remote control. Hackers can target these apps, gaining access to your car through compromised accounts or security flaws in the app itself.
Top Methods to Block Key Fob Signals: Effective Solutions and DIY Options
Now that you understand the risks, let’s explore various methods on how to block key fob signal, ranging from simple home remedies to dedicated security products.
Convenient but Less Reliable Methods
These methods are often mentioned as quick fixes, but their effectiveness can be questionable.
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Aluminum Foil: Wrapping your key fob in aluminum foil is a commonly suggested DIY method. The idea is that the metal will block the radio waves. However, standard household foil is often too thin and lacks the density to completely block signals reliably. Furthermore, it’s inconvenient and impractical for daily use.
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Aluminum Tin Can: Similar to foil, placing your key fob in a metal tin can is another home-based suggestion. While a tin can might offer slightly better shielding than foil due to its thicker metal, it’s still not a guaranteed method for consistently blocking key fob signals. Its practicality for everyday carry is also limited.
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Refrigerator or Microwave (Unplugged!): Storing your keys in a refrigerator or (unplugged!) microwave is based on the principle of using metal to block signals. However, these appliances are not designed as Faraday cages, and their shielding effectiveness can vary. Moreover, there are potential risks of damaging your key fob due to temperature or humidity changes within these appliances. It is strongly advised against placing your key fob in a microwave that is plugged in or could be accidentally activated.
Faraday Bags and RFID Wallets: A Step Up in Protection
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Faraday Bags: Faraday bags, or signal-blocking pouches, are specifically designed to block electromagnetic fields, including radio waves. They are typically made with layers of metallic fabric. These bags offer a more reliable solution than foil or tin cans and are designed for the purpose of blocking key fob signals. However, the quality and effectiveness of Faraday bags can vary significantly. It’s crucial to choose bags from reputable brands and, ideally, test their blocking capability. Some cheaper bags may have inconsistent shielding or only block signals in one pocket of a multi-pocket design.
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RFID Wallets: RFID-blocking wallets, designed to protect credit cards from electronic skimming, can also be used to block key fob signals. They are more compact and convenient to carry than Faraday bags. Similar to Faraday bags, the effectiveness of RFID wallets depends on their construction and materials. Look for wallets specifically tested and certified for signal blocking. Always test any Faraday bag or RFID wallet to ensure it effectively blocks your key fob signal. You can do this by placing your fob in the bag/wallet, moving away from your car, and attempting to unlock it. If the car remains locked, the signal is likely blocked.
Disabling Keyless Entry: A Drastic but Effective Measure
- Deactivation of Keyless Entry: For ultimate security, consider disabling the keyless entry feature altogether. This is a drastic measure, as it eliminates the convenience of keyless entry, but it also completely removes the vulnerability to relay attacks. Consult your car’s owner’s manual or your dealership to see if this is possible for your specific model and how to do it. Disabling keyless entry means you’ll have to use the physical key buttons on your fob to lock and unlock your car, or in some cases, use a physical key in the door.
Investing in a Secure Key Fob Solution
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Secure Fob Chips and Upgrades: The most advanced and reliable approach to blocking key fob signal involves using technology designed specifically for this purpose. Secure fob chips are designed to enhance the security of your existing key fob. Some innovative solutions involve chips that deactivate the fob’s signal when it’s not in motion for a certain period (e.g., after 3 minutes of inactivity). This motion-sensing deactivation prevents relay attacks by ensuring the fob only transmits a signal when it’s actively being used.
These secure fob solutions aim to provide seamless protection without sacrificing the convenience of keyless entry. They often offer additional benefits like extended battery life for your key fob by reducing unnecessary signal transmission. When choosing such a solution, ensure it is compatible with your car model and comes from a reputable manufacturer with positive user reviews and ideally, independent testing or certifications.
Conclusion: Taking Control of Your Car’s Security
Understanding how to block key fob signal is essential for any owner of a car with a keyless entry system. While convenience features are appealing, they come with security considerations. Choosing the right method to block your key fob signal is a crucial step in protecting your vehicle from theft.
From inexpensive DIY methods to more reliable Faraday solutions and advanced secure fob technologies, various options are available. Evaluate your needs, budget, and desired level of security to make an informed decision. Don’t leave your car’s security to chance. Take proactive steps to block your key fob signal and enjoy greater peace of mind knowing you’ve taken measures to deter modern car thieves. Invest in a robust solution today and safeguard your vehicle and your peace of mind.
