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Dead 12-Volt battery

Discussion in 'Gen 4 Prius Technical Discussion' started by Ty D, Nov 3, 2021.

  1. Ty D

    Ty D Junior Member

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    Four
    Opened back door last night and noticed headlights came on; thought it was just a Prius feature. This morning I tried to start my car and it wouldn't start and displayed message, "low 12-volt battery, apply parking brake securely while parking. SEE owner's manual." My 2018 prius would not start and I kept getting a clicking sound. Lights and everything was just clicking. Called my insurance company to jump start but yet the message still appears. Please help. I bought a warranty back in 2019 when I purchased my used Prius. Is this a defective battery?

    Posted via the PriusChat mobile app.
     
  2. Hidyho

    Hidyho Senior Member

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    Simple fix, replace 12v battery in engine compartment, should be between $160 to $200, some auto parts places have it, and of course dealership, I got mine through dealership and worked my way into a discount of $165 by telling them I could get it cheaper at Interstate Battery, which was true. You will save money by taking old battery with you, easy to get out. You would have to tow to dealership and they would overcharge you to replace if you have it done that way. Final note, battery warranty for a new car is usually only the first year for full replacement and prorated after that, new battery will have new battery warranty per whatever the battery has, my factory battery had no real value after 3 years, new one has 2 years full replacement, 1 more year 50%.
     
    #2 Hidyho, Nov 3, 2021
    Last edited: Nov 3, 2021
  3. alanclarkeau

    alanclarkeau Senior Member

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    What country are you in - (it just shows a random number). Different countries have different features, even with headlights.

    Odd that the headlights came on. What position was the Headlight Switch?

    Which back door did you open - a passenger door, or the boot?
     
  4. burrito

    burrito Active Member

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    BTW, boot = trunk/hatch
     
  5. Hidyho

    Hidyho Senior Member

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    I believe he is using his Zip Code, which makes him just outside Atlanta, Georgia.
     
  6. Hidyho

    Hidyho Senior Member

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    Common experience with a 12v battery going bad or bad, almost all those happened to me when mine went out.
     
  7. alanclarkeau

    alanclarkeau Senior Member

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    The headlights coming on when he opened "the back door" - didn't add up.
     
  8. Hidyho

    Hidyho Senior Member

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    Yeah, but lots of weird stuff happened to my Prius when the 12v died, including strange lighting things. Its a simple dead battery, change it and all is well.
     
  9. AzWxGuy

    AzWxGuy Weather Guy

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    At the other end of the car we have what us Yanks call the hood, which is of course the bonnet. I learned all these marvelous terms with my first car, a very fine British Leyland product.
     
    alanclarkeau likes this.
  10. burrito

    burrito Active Member

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    I learned from my wife: also a British product, but not quite as fine as the Leyland variety.
     
    AzWxGuy likes this.