What hurt is done if car is left on overnight

You can avoid this by just pressing the Power button to turn the car off--which also puts the car in park, so there's no need to first press the Park button.

 

No harm, but, as was already mentioned, can be a safety hazard.

I second the idea of using the POWER button instead of the PARK button. Take that moment before you jump out to look at the dash to make sure all the pretty lights are off.

 

Obviously you will burn a little gasoline.

Tom

 

the car itself consumes more power while sitting on than the radio.. or headlights.. or any of that combined. you probably burnt about a gallon. if the climate control was off, it's about a gallon every 12 hours.

 

I agree with stream. Get use to pushing the Power button rather than the Park button while shutting the car off.

 

I'll make it unanimous (so far.)
No harm done to the car.

If you're apt to do this again, you may want to get and use a carbon monoxide detector for your home and for the garage.
Like others, I use the POWER button to shut down the car when I'm finished with it instead of Park + POWER.
YMMV.

Good Luck!

 

Get in the habit of hitting the power button instead of park button AND lock the car. You will be unable to lock it if it's not shut off. Two safeguards to ensure it doesn't happen again.

 

Not sure if this helps but I alway keep the key inside my pocket and lock my doors.

 

As others have said the big hurt could be to you or others in the house, especially if there is a bedroom adjacent to or above the garage. I'd second the call for a carbon monoxide alarm - it is $25 or so well spent.

 

Always locking your Prius is a good idea. I live in an area where locks are unnecessary, but I always lock my Prius. Locking is a quick and effective way to ensure that all doors are fully shut and the Prius powered down. If not, your Prius will beep and refuse to lock.

Tom

 

FWIW, the car can be locked while on if you use the physical key, rather than the door button or the fob button. This is useful for heating the cabin in bitterly cold weather.

Damage to the car by leaving it in Ready would be if you were low enough on gasoline that the car ran out of gas, and then the traction battery became depleted.

Develop some kind of routine, whether it's always using the Power button, as some have suggested, or always locking, as others have suggested, or keeping the fob in your pocket, whatever. But get into a habit that becomes second nature, to make sure you always turn the car off. I believe that if you have the fob in your pocket and you close the car door from the outside, the car will beep at you if it's still on.