Well I always kinda wondered how far away I could be from my car after it had been started and I had the key in my pocket... WEELLLLL....I loaned my car to a co-worker to go to the mall when I get a cal that went something like this... her "did you by any chance forget to give me the key?" me <slapping forehead> "oh damn!!!" long story short she was over 10 miles away from the key in my pocket and it just kept on running so I figure once it's started, it's started...
Yes, the car will stay on if you walk away from it with the key. However, when you close the door, it will beep 3 times and the amber car wtih the ! in the middle will come on on the dash. I suppose Toyota felt this was safer than causing the car to shut down on the highway because SKS failed.
I always love it when my wife quietly leaves her purse in the car (with HER key in it). When I try to lock the door, Dora protests with several beeps leaving me to figure out what the problem is.