Do I need to screen my keyless car key when I'm at home?

If a key has a button to open the car door and you press a different button to start the car, do you need to screen the key when at home?
If you're asking if you should take some precautions to prevent keyless car theft because your car has a start-stop button, we would always advise yes. Thieves use relay devices to amplify the signal from the key fob in your home to a transmitter near your car, which essentially tricks your car into thinking the key is present. This allows them entry into the car, where they can use the start-stop button to start the car without the key. The key also doesn't need to be present within the car for it to continue running - so they can keep driving as long as the ignition isn't turned off at any point. As far as we're aware, any keyfob is vulnerable so if your car has keyless entry and start then it's a good idea to buy a signal blocking pouch for the keyfob. Or you can wrap it in tinfoil (or put it in a metal box).

The metal within the wallet should act as a Faraday bag, effectively doing the same job as the aluminium foil - which suggests there's an issue with the bag sealing. We've tested the Monojoy faraday bag on multiple keyless entry cars and it's always worked flawlessly, but the wallets/bags don't block signal if there's any kind of opening. Therefore, if the velcro isn't fully closed up, or there's a hole on the metal interior layer, or the key is put inside the wrong part of the pouch (which some people do) then it doesn't work as it should. Our review is here: kit.honestjohn.co.uk/reviews/review-monojoy-keyles.../
Answered by Georgia Petrie on

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