I have been known to lose my car keys, and my spouse known to lose them a lot more often. When this happens in town, I can just get the spare key from home and bring the car home. I have my email address stuck on each Prius key fob, so it will probably find its way home. But what happens when the key is lost 500 miles from home? I have a solution. The electronic key is a radio transmitter, so it's not a good idea to hide the spare one in the car unless it's disabled. A quick and easy way of silencing the transmitter is to wrap the key in double-thickness aluminum foil. This package can then be hidden in one of the Prius's many hiding spots. How to get inside the car to reach the electronic key? You may get someone such as the AAA with a slim-jim to open the door, or you can get a copy of the physical metal key made and carry it in your wallet, which is what I do.
Your idea is probably a few years late. Since Prius had SKS key, this idea had been discussed. A mylar bag (the kind that is used by Fastrek transponder in Bay Area) would also work instead of aluminum foils. I would also suggest you hide the spare key inside the rear bumper. A few plastic clips (from below) can be removed with finger nails to access it when needed. No need for slim-jim. Thieves will not try to find your spare key inside the bumper.
why even hide the whole key outside? they are rather costly. If I were actually going to dedicate one of these guys to spare-in-car I would just pull and hide the little driverside door key someplace on the body and store the rest of the key inside.
"... How to get inside the car to reach the electronic key? You may get someone such as the AAA with a slim-jim to open the door, or you can get a copy of the physical metal key made and carry it in your wallet, which is what I do." I think having an extra metal key in wallet is a great idea! How / where did you get the key duplicated?
As for my wife, she doesn't take the time to be organize. she puts them where ever. Once she lost the keys to the store she managed, had to pay a pretty penny to have new ones made. 3 months later while changing the car oil, I grabbed a "rag" from the "rag bucket" ( old shirts or dress pants) I hear a jingle.... There were her old store keys in the pocket of her pants that had spilled bleach on.
