I have a 2015 Prius with about 110K miles on it. It has been a trouble-free dream. It has not been driven as regularly since the pandemic, and we have been experiencing a few weeks of pretty cold temps (for us; down into the teens at night, high 20s during the day). Last week, the car would not start (the dash lights did turn on, but it would not start). We put a batter charger on it and it started right up after a few minutes. I drove it down the block and back, then for the rest of the week, I started it every or every-other day. Today it is completely dead again - dash lights won't even respond this time. I think I need to just replace the 12v battery. I also need to replace my key fob battery - but cannot find the correct type of CR1632 batter at the 3 places I've looked in town. Frustrating, but I don't think this is the source of the problem. So my issue is - I live 40 miles away from the nearest Toyota dealer where I normally do all my maintenance. I plan to take it there to get the 12v battery replaced. Assuming I can get it charged up again, is it okay to drive that 40 miles (about 40 minutes, highway speeds of 70mph, up and down hills) or is this dangerous? Is the car at risk of stalling during a drive with a sickly 12v battery? Thanks for the advice.
"It has not been driven as regularly since the pandemic," Is the problem. Go to an auto supply and have the battery load tested. 90% you need a new one. Then keep it charged.
once started, the inverter takes care of the 12v needs. you'll be fine. you can also jump start from another car, or a lithium jump pack
No guarantee but it likely will be fine. Call them first to be sure that they have a battery in stock......and so they can have it charged up before you get there. There is really no "need" to have this done at a dealership. Many auto parts stores might do it too. Make some calls......and save yourself several hours. Maybe some $$$ too. Wherever you get the new battery, it MUST be fully charged before install.......or immediately after. You can't depend on the car to charge it up if it's not close to start with.
That'll kill a 12V in no time. It takes a LOT more than just a drive down the block to recharge what bled off sitting idle and got used starting up the computers and closing the relays. Short drives like that will just pull the battery lower and lower. Most any auto parts store should have a replacement battery, although the one from Toyota is a fantastic battery. And then do what @rjparker recommended and keep it on a charger till you're ready to drive normally. The fob battery is a CR2032 and is available anywhere batteries are sold. The 1632 is a little smaller in diameter. I wonder if someone put in the wrong one at some point. https://parts.olathetoyota.com/blog/9087/how-to-change-prius-key-battery
Measure voltage first thing in the morning with a digital meter, post the result. Better: Most automotive retailers selling 12 volt batteries will have a pro-level electronic load tester, can assess the battery’s viability, usually for free. You can do the test yourself with a pro-sumer level tester, like Solar BA9. A healthy battery will show voltage at least 12.5, and Cold Cranking Amps at least higher than spec, typically 50+ or more.
You linked to a Gen 2 instructions. Gen 3 is a CR1632 (as you posted yourself in Battery for Gen 3 remote | PriusChat )
