Are faraday bags useful to stop keyless entry theft?

Are faraday bags for car keys viable? Surely when the key is removed to enable the engine to be started it becomes vulnerable to hacking. Also, once started my car will continue to run even when I move away from the car.

Asked on 26 February 2018 by yaesu

Answered by Honest John
Yes because you only need to block the signal from being boosted when you're away from the car. If you are in the car then the only way they can steal it is to hijack it, which they could do with any car. Best to shut off the engine at the button, then lock the car with the key signal close to the car and only then put the key into the Faraday bag so its signal is blocked.
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