I got a phone call that my GF's daughter had come down with a migraine and was parked by the side of the road a few miles from my house, essentially blind and unable to drive. I take my Mom with me in the TCH and we drive over to rescue the girl.

We pull up behind her car, I get out of the TCH, hold the driver's door to help my Mom to get in and close the door for her. Then I walk forward to my GF's daughter's car, climb in, start it up, and drive home with my Mom following me.

Here's what's weird - I forgot to take the smart key for the TCH out of my pocket and leave it with my Mom. She was able to follow me all the way back home, going the entire way with "Key is not detected" on the MFD. So what are the rules for driving without the smart key? I was surprised that it could be done at all. Are there any hidden security risks if you forget to turn the car off when you get out, like someone could get in and drive away?