Hello, I have a 08 prius and every now and then when I shut off the car I hear the tiniest little beep and I can't figure out what it is. It isn't my FOB as I've already had that beep and fixed it over the summer. It has been going off and on for the last 2-3 months, I can't make it happen on purpose so the dealership thinks I'm losing my mind and no its not my cell phone beeping either lol it is definitely the prius beeping
check the 12v battery. Check in the morning before starting. I use a multi meter and like to see 12v +. If below12v then replace it asp. H