My 12V Battery is dying

Discussion in 'Gen 5 Prius Care, Maintenance and Troubleshooting' started by priusasa, Dec 13, 2025 at 11:39 PM.

  1. KH111

    KH111 Member

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    Sorry if I was testy, I will try it again and see if I can fit the screwdriver in as depicted and not just use my fingers to move the cover out of the way.

    KH
     
  2. VelvetFoot

    VelvetFoot Active Member

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    At least the rear doors have the mechanical backup unlock buttons.
     
  3. KH111

    KH111 Member

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    Oh, and the replacement TrueStart H4 EN LLW battery lists for $344 (US). Fortunately covered under warranty.

    KH
     
  4. VelvetFoot

    VelvetFoot Active Member

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  5. KH111

    KH111 Member

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    Damn, great reminder. Not sure I even knew about that.

    KH
     
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  6. VelvetFoot

    VelvetFoot Active Member

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    More 'research' is required, but I bet those buttons don't work if there's no electric.
     
  7. ChapmanF

    ChapmanF Senior Member

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    I think there was a thread here not long ago where somebody climbed out a window just because the electric door unlock didn't work.

    That would be a big change from any generation I'm familiar with, where the movable buttons (with the orange unlocked indicator) above the door handles have always been purely mechanical.
     
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  8. KH111

    KH111 Member

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    I just tried that button and it worked but it felt purely mechanical in the action. I was barely able to do it. Seems unlikely they would have 2 electrical switches to open the door, defeats the purpose of having a backup.

    KH
     
  9. VelvetFoot

    VelvetFoot Active Member

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    But it wouldn't let you in the car with all the doors locked, would it?
    edit: I just answered my own question. No it wouldn't. :)
     
  10. BiomedO1

    BiomedO1 Senior Member

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    I believe someone here mentioned that a Tesla was electrical and there was an emergency escape cable handle behind a speaker panel door that you had to pry off.
    IMHO; reading the OPS manual may save your life, if you remember it's there. Imagine being in a accident and having the main breakers pop - NO electricity. So someone outside can't even help you because they're locked-out and your locked-in. Always nice to have a mechanical alternative or someway of hooking up an alternative power supply to open the doors.
     
  11. KH111

    KH111 Member

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    You are right. Otherwise anybody could push that mechanical release and get in the car so now I am starting to question the design of the damn thing in the first place.

    KH
     
  12. VelvetFoot

    VelvetFoot Active Member

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    There's probably some scenario where the doors are unlocked, but the electrical latch doesn't work for whatever reason. Ice?