Oh, yes, it's a different kind of attack! (What I thought about is recording your key's transmission and replaying it later.)
For this, I'd opt for a button on the key; it's still better than not forgetting to put the key to a Faraday cage. Cutting the power circuit and adding a button that restores it must be much simpler that refitting the entire car's locking system.
There's already a button on the fob to unlock the doors. The proximity unlock is a separate feature. The whole point of the proximity function is to remove the need to push a button on the fob. Your idea makes no sense, unless you're proposing deletion of the proximity unlock feature.
Yes, I'd like to remove or severely limit this feature. When it's always on, and it does not properly check for proximity of the key, it's broken by design.
I'd rather have a button that allows for proximity unlock during 1-2 minutes after pressing, much like Bluetooth public visibility.
If I had an existing key with this proximity misfeature, I'd like to modify it as I described: having press a button to unlock my car is for me preferable to a risk to have it stolen.
So you'd like to take the fob out of your pocket, push a button to enable proximity unlock for a brief interval, place the fob back in your pocket, and then have the door unlock when you approach the car?
