12 volt battery dead and confused by so many different perspectives.

Discussion in 'Gen 1 Prius Plug-in 2012-2015' started by Tia314, Dec 10, 2025 at 4:40 PM.

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  1. Tia314

    Tia314 New Member

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    So, I don't know where to start and don't want to get into a lengthy story.

    2015 Prius Plug-in Advanced.

    12v battery dead. Call AAA several times and have gotten different perspectives/ guidance. First guy didn't have battery, told me to take it to Toyota.

    Completely dead and can't put into neutral. Secong AAA guy said he would just drag onto flatbed regardless and I said no.

    Third AAA guy (all from same company) said they don't replace the batteries because all hybrid batteries have to be replaced simultaneously.

    So, I don't know how to get the car towed.

    I was going to try to replace the 12v myself, but is that not ok???

    This is driving me nuts. I bought this car on August 1st and haven't really been able to drive it. :(

    Thank you
     
  2. priumium

    priumium Member

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    You can easily replace this battery yourself. It’s a gen3, that requires less removal of trunk compartments.

    Just search YouTube and order or pick up a battery, or a 12V charger. But if the battery is fully depleted it will never be the same. Go for a new battery. It does not have to be fancy.

    Save the old one and get a cheap 12V charger to have a emergency backup one if it accepts charging.
     
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  3. VelvetFoot

    VelvetFoot Active Member

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    Of course this assumes you can get anywhere without the car, lol.

    You could get a jump pack (battery) from Harbor Freight, or similar, or, you could wait for Amazon to deliver one if you were stuck at home. (I accidentally signed up for Prime with 2-day delivery, and it is great. Too bad it costs money, lol.)

    Read the instructions, get the car going, and go get a new battery and have them put it in while you wait.
     
  4. VelvetFoot

    VelvetFoot Active Member

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    Plus, I'm surprised AAA didn't use a jump pack to get it started.
     
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  5. BiomedO1

    BiomedO1 Senior Member

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    Welcome:
    There's a lot of misinformation about these car and I'd double-check whatever someone tells you. The absolute best source of information is your OEM operations and quick-start manual. I believe you can download a copy from Toyota for free and do a key word search.
    IMHO; Just jump-start the car to get her home or to a mechanic. DO NOT take the car out of 'Ready' mode until you get to your destination - otherwise you may need another jump to restart. There's a jump-point under the hood in or near the drivers side fuse panel. Again, the OEM manual is your friend! Even here, there's a few people that will steer you in the wrong direction - always double-check the information against a valid source (OEM manuals). I know it's a pain, but if you want to cut through the BS - that's what you have to do.

    Good Luck......

    PS. the batteries may be replaced independently (traction pack vs starting battery). Sorry, just re-read your post - how long has that car been sitting there - undriven? I believe the OPs manual states to run the car at least once every 30-60 day for an hour or two to keep things running properly. There's a procedure for parking a car like this long-term. If that traction battery dies; your not going to be able to start the car. That's a $3K mistake.
     
    #5 BiomedO1, Dec 11, 2025 at 10:59 AM
    Last edited: Dec 11, 2025 at 11:32 AM
  6. bisco

    bisco cookie crumbler

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    i can't believe the car has been sitting since you purchased it over 5 months ago, you posted yesterday and haven't come back even though it's driving you nuts. where is it?

    1) don't let them drag the car, unless they are dragging it to the junk yard

    2) don't confuse the 12 volt battery with the hybrid battery

    3) go to toyota and buy a 12 volt battery, ask them to test it before leaving

    4) open the hood and connect it with jumper cables to the jump point and ground. this will allow you to open the hatch

    5) alternatively, you can crawl into the hatch from the back seat and use the emergency release

    6) remove the old battery, install the new one:search

    7) start the car, or even better, charge up the hybrid battery with the evse if you are near an outlet
     
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