2005 prius 223,000 miles I was stuck in traffic for 2hours. I turned the car off, then unto electrical only but left my lights on. I had great trouble getting the car to start. The display faded and the wipers weresuperslow, Is this a 12 v battery problem? Are there 2 - 12v batteries, one under hood, one in trunk with the traction battery? I have never replaced a battery in this car. I am in Canada and wonder where the best type and source of a battery to replace the original., if this is indeed the problem. Thanks for the advice.
Only one 12v battery (in the boot/trunk). You should have left the car on in the "ready" state. The the engine would have run to recharge the HV battery and the converter would have been able to keep the 12v charged also.
You have just one 12V battery, and it's in the back of the car, along with the traction battery. The 12V battery has a very small capacity, as its main job is to boot up the car when you start it, and you should never keep the car in Accessory mode (which I assume is what you mean by "electrical only") for more than a few minutes, as the 12V battery will soon run down. If you're stuck in traffic, or whenever the car is stopped but not turned off, you should stay in Ready mode, as this will keep the 12V battery charged, and the engine will start as needed in order to charge the traction battery. That said, if you have a 2005 and this is the original 12V battery, it's well overdue for replacement. There are lots of threads on the forum about this, but perhaps someone in Canada can make a specific recommendation for you.
Sure sounds like it's time to get a new 12v battery. There's only one in the back. SCH-I535 Here's another thread with links to replacement batteries: 12V battery going bad? SOLVED | PriusChat SCH-I535
yes, you need a new 12v. there is only one, in the trunk. you can get a replacement at a toyota dealer, or auto parts store. look for an optima yellow top if you choose the latter.
Two hours with the headlights on will discharge any battery. It will take 50 some miles of driving to fully recharge the 12v battery. After it's fully charged I suggest you check its voltage. This can be done using the center screen on your car. You can find the procedure here on Prius Chat. You may not need a new battery.