Maybe this is on the forum somewhere but I couldn't find it. I wanted to leave my Prius powered-on on a cold winter day to keep my dogs warm. I kept getting defeated by the feature that prevents the doors from being locked when you get out of the vehicle with the engine running. I finally stumbled on this method. Power-on the Prius. Get out and shut the door. Lock the door with the key(not the remote lock, the little key in the Smart Key fob.) You will have to unlock the door with the key as well. The temperature stays at about 50 degrees with the temperature setting on LO. This is working well for me but I wonder if anyone knows of a reason why it might be detrimental to the Prius? Thanks!