I have a Corolla with the smart key and heres the answers to your questions:

The car will only start if the key is detected to be inside the cabin. I tried before to leave the key on the outside roof and it wouldn't start.

Second, you cannot lock the car with the key fob or smart key button on the door handle if the engine is running. I have not yet tried to press the lock button on the inside of the door and then closing it.

Lastly, the car will automatically apply the parking brake if brake hold on the electronic parking brake is active and you take your seatbelt off. The car will still be in drive with the engine running however.

 

FrankieG13 is correct. I’ll add that the range that it detects the key to unlock the doors is just a couple feet. And it’s also dependent on which door you walk up to. So if you walk up to the driver side, it cant be unlocked from the passenger side, and vise versa.

Here’s the pages of the manual that explain this.

 

OK this gives me a bit of peace of mind. I remember reading on this subject when these were less popular (ie. years ago) and people had found ways to boost signals and such to break into cars and steal cars. Now I'm obviously going to be putting my car in the garage most of the time as well, so that's just an extra layer of protection against theft. So I'm thinking either the key has such a low transmission rate that it can only travel a few feet. Either way I'll probably buy one those Faraday bags anyways for when I travel just to be safe.

I know that once you start the car, you can drive away (from wherever the key is) although the car will warn you and once you turn the car off, you won't be able to restart it (dealer did that once on one of the test drives and said just don' turn the car off during the test drive.)

 

people had found ways to boost signals and such to break into cars and steal cars.

Actually for a highly motivated and, above all, very well techno equipped thief, it's possible to intercept key fob code if very close to it - like in a compact crowd (same for contactless "smart" credit cards) or to throw tons of random codes near the car until one works. That's in theory. Odds of it happening in real life are quite low.

 

Yeah probably are not very likely. I mean if it was super easy for an average person to gain access to cars, car companies would either be forced to change their technique for abandon keyless entry or at least "smart" key technology (push button start, or "smart key" unlock/locking doors).

Although I do recall when test driving one of the cars, the salesmen still had the key in his pocket and he was standing about 10-12 ft from the car so it said it couldn't find the key so that's a bit reassuring I that after a small distance, the car can't be opened or started. Maybe I'm just a bit old fashioned as all of my vehicles have required physical keys to start the vehicle (although I've had keyless entry with a clicker).

I sort of wonder how this "Smart" key stuff works though... does the car identify the key via some electronic signature, along side just the frequency it's operating on? I mean it almost would have to be especially if you had two identical vehicles sitting next to each other with different keys but both have the Smart Key system.