Putting your car keys in the fridge is a method some people use to protect their keyless entry system from being hacked or stolen via a method known as a “relay attack.” Here’s why this technique is considered useful:
1. Signal Blocking
- Keyless Entry Systems: Many modern vehicles use keyless entry systems that allow you to unlock and start your car without inserting a key. The key fob constantly emits a signal that your car recognizes when you’re nearby.
- How Relay Attacks Work: Thieves can use devices to intercept and amplify the signal from your key fob, even if it’s inside your home. By capturing this signal, they can trick your car into thinking the key fob is close by, allowing them to unlock and start your car.
2. Faraday Cage Effect
- Metal Containers: The idea behind putting car keys in the fridge is that the metal lining of the refrigerator acts like a Faraday cage, which is a structure that blocks electromagnetic signals. This can prevent the key fob’s signal from being intercepted and used by thieves.
- Signal Interference: By placing your keys in the fridge, you’re essentially blocking the signal from being transmitted beyond the fridge, making it harder for thieves to amplify and use the signal to steal your car.
3. Practicality
- Accessibility: While wrapping keys in aluminum foil or using a Faraday pouch is also effective, putting them in the fridge is a simple and convenient option. Since most people have a refrigerator, it can be a quick solution to protect your car keys without needing to buy anything extra.
- Cool Environment: Unlike other electronics, key fobs don’t contain components that are particularly sensitive to cold temperatures, making the fridge a safe place to store them temporarily.
4. Temporary Solution
- Short-Term Protection: While putting keys in the fridge can be a useful short-term solution, it’s not necessarily a practical long-term habit. For continuous protection, a Faraday pouch designed specifically to block signals might be more convenient and portable.
