I often have a need to lock the car but leave the keys inside and use the manual unlock to get back in. This might be when I go diving or swimming and have nowhere safe to store the key but also don’t want to take it in the water with me.

I’ve tried doing this by turning off KESSY, which mostly works except when I do unlock alarm goes off.

Have you tried putting the keys in a tin box (aka Faraday cage) when you leave them in the car.

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