The disturbing increase in sophisticated car hacking methods makes protecting your car from electronic thieves more critical than ever. According to the New York Times, keyless entry systems are more vulnerable than you think, forcing car owners to look for effective solutions. A top recommendation that any good car key locksmith would make is the Faraday box. These devices disrupt the relay hack method criminals use to gain unauthorized vehicle access by blocking the radio signals emitted by car key fobs.
The good news is that creating your own Faraday box is easier than expected, providing you with a cost-effective and fully customizable solution that can enhance the security of your vehicle. Read on to learn more about how Faraday boxes work and get quick instructions on making your own DIY Faraday bag.
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The Mechanism Behind Faraday Boxes
To understand how these devices work, it’s important first to familiarize yourself with relay theft. This method is commonly used to steal vehicles with keyless entry systems. These systems operate by recognizing short-range radio waves emitted from key fobs. In a relay attack, two thieves work together using a signal amplifier to boost the radio signal from the key.
Next, with the help of a signal transmitter, the crooks will pick up the signal, impersonate the genuine key, get into the car, and drive off with it. For all these steps to occur, car thieves must pick up the signal inside your house, where the keys are located, usually next to the front door or kitchen. By cleverly pointing the amplifier in the right direction, they can pick up the keyless ignition car’s signal from the key from a remote distance without having to break into the house and manually grab the keys.
The Faraday box or bag can successfully prevent this from happening. It blocks the signal from the key and prevents it from leaving inside the box, making relay theft almost impossible. The main idea behind these boxes and pouches is identical to the more popular Faraday cages. They are both enclosures designed to stop signals from entering or exiting the inside of the respective box or bag.
How to DIY a Faraday Bag
Carefully choose your favorite top-quality conductive fabric, as its purpose is to block all electromagnetic signals by creating effective shields. You will also need a sewing kit to turn the raw materials into a fully functional Faraday bag. Make sure it includes threads, needles, and sewing accessories you need to craft the layers.
You will also need a pair of sharp scissors and a quality zipper or Velcro to create the closure mechanism that will seal the bag and leave zero room for electromagnetic penetration.
Start by measuring the fabric to the desired size of the bag. Consider how many keys you want to store inside. Carefully cut two identical pieces of fabric for the inner and outer layers of the bag. Sew the inner layer with the conductive fabric to ensure functionality. Sew three sides of the fabric together and leave the top open. The seams must be secure, so do not leave any gaps. You can also add pockets to the inner layers to store several key fobs.
The Faraday effect will only work if you have an effective closure mechanism at the top of the interior layer. For this, use either velcro or sew a zipper; just make sure that it effectively closes this layer. Next, sew the outer layer with decorative fabric for a more aesthetically pleasing effect. For this, sew together three sides of this fabric and leave the top open to match the design of the inner layer.
For the final step, assemble the DIY Faraday bag by perfectly placing the inner conductive layer inside the outer layer, ensuring they align along the open edges. Stitch around the bag’s top edge to fasten the layers together and trim all the excess fabric for a more polished look.
Consider using aluminum or copper or aluminum but steer clear from anodized aluminum. If you want to use a mesh, see that the holes are smaller than 1/10 the signal’s wavelength. For example, in North America, car remotes send their signal at 315 megahertz, corresponding to a wavelength of approximately 0.95 meters. This means a mesh with holes smaller than 9.5 centimeters should function fine.
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Make a Faraday Box
You could also try a simpler DIY method by making your Faraday box. Usually, Faraday boxes are built with a type of metal lining, the specific materials depending on their manufacturer. However, you can make an effective Faraday box by lining a small box with at least three layers of aluminum foil.
For this model, you will also need to cut and lay 5mm aluminum mesh on the bottom of the box and its sides, ensuring that you overlap them by a couple of inches. Use some wood staples to keep them in place, then lay two layers of mesh while overlapping the holes in between them so they are even tighter. Once the key fob is placed inside the new DIY Faraday box, the touch-to-open access of the car will stop working, thus preventing potential thieves from using the relay theft method. While a box lined with aluminum foil might give better car protection and reliability results, a nicely designed mesh box is also expected to work well enough, so the choice is ultimately yours.
Final Thoughts
Creating your own Faraday box is a straightforward, cost-effective approach that offers full customization and enhances your vehicle’s security. By understanding how Faraday boxes work and following simple instructions to make your own DIY Faraday bag, you can significantly improve the protection of your vehicle against relay theft and other electronic attacks. To stay ahead of car hackers, consider taking proactive steps to secure your vehicle. You can also contact a reliable automotive locksmith for additional car security tips or practical assistance with your key fobs, car locks, ignition cylinders, or any alarm and security device.
Related: Avoiding DIY Disasters: Why Professional Locksmiths Are Essential for Home Security