I went to drive to work today and found that my battery was drained. None of my interior lights were on and I'm 100% sure I turned the car off last night after I backed it into the garage. Last night I drove the car home and was mostly on EV, but drove the last 3-4 miles on ICE. I had the car charging overnight too. This morning, with the battery dead and the cable plugged in, it was making a click sound near the fuse box when I tried to start it. The passenger seat's heater was on (I think) and I don't think any of the doors were ajar. The only door that could have been opened would be the driver's but I don't think it was half closed. I ended up calling ToyotaCare and a guy came to jump the car. When I turned on the car, I had 11.2 miles on EV and a full tank of gas. I'll check the battery's voltage tomorrow morning, but I'm a bit at a loss at why/how the car would be drained. Even if by some chance I left the car on, wouldn't the ICE turn on? Would the interior lights drain the whole 12V battery although the car was being charged? Any thoughts?
you didn't leave the car on. if you had, there wouldn't be any problem unless you ran out of gas. you left something on, or the door ajar and drained the 12 volt. not while being charged, but after charging finished. it's small, and drains quickly. try plugging it in, and see if that charges the battery enough to start it. if not, you'll need a trickle charger, and then regular testing to make sure it isn't damaged. either way, it should be under warranty.
If I left a door or light on, wouldn't it drain from the 2nd battery that's being charged? Or does it drain off the 12V? If it was the 2nd battery, it should constantly recharge itself as it got low since I had it plugged in all night.
the hybrid drive battery is the one your charging. the 12v gets charged at the same time if it needs it, and also while your driving. the hybrid drive battery is not connected to anything until you make the car ready, which requires a healthy 12 volt. if, for instance, a door is ajar, you'll be fine until the hybrid battery is finished charging. then the 12 volt no longer is getting a charge, and believe it or not, the dome light can drain it fairly quickly. then, when you get in and press the power button, nada.
Seat heaters are only active in 'on' mode (all electrical accessories active but hybrid (traction) battery disconnected) and of course in 'ready' mode, they are inactive in accessory mode or when off. If you are sure you shut off the car than it's not the seat heater that caused it.
I wonder how much of a battery drain the dome light is. By the way, thanks for the responses! It's always great to understand more about this car.
Having a door ajar overnight can run the 12 volt battery down to near drained. Maybe it's more than one light: the (two) map lights, and the "dome" light. At least on ours, a door ajar will also turn on: the foot well lamps, the door sill lights, and the door courtesy lights. It's an effing Christmas tree, lol.
I had a sun visor flipped down with the little door open so that the sun visor/vanity light is turned on. I didnt notice it was on during the day time, but that vanity light will turn on even if the car is off (as long as the little door is slid open). That light, itself, drained my 12V battery (and this was when my car was only about 2 years old).
