How long will the battery last if car is left running, but not moving?
I don't own a Prius, but isn't there a power bar that is on the dash that shows the level of the battery charge? I know the more accessories you have on, the fast it will drain. I don't think you have a specific amount of time that you can calculate. Try timing it and see how long you can go to get a good idea.
Should last until you run out of gas,if battery is good and alternator is good all so.
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