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12v battery showing 10.6v in diagnostic mode

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by antonio-kauai, Oct 25, 2017.

  1. antonio-kauai

    antonio-kauai New Member

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    2004 Prius
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    I just got a 2004 Prius that had some minor front end damage (bumper, headlight and fender). I just followed a tutorial about how to get into diagnostic mode to check the 12v battery.

    Its showing that its hovering from 10v to 10.6v.

    Is this a sign that I need to get a new 12v battery?

    Also, is there a specific type of 12v battery I need to get?

    Also, is it fine for me to drive it until I have the funds (and until it gets shipped to me)?

    Thanks,
    Antonio
     
  2. bisco

    bisco cookie crumbler

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    welcome!
    yes, yes and maybe. no knowing when a low 12v will totally quit.
    all the best!(y)
     
  3. ChapmanF

    ChapmanF Senior Member

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    Vehicle:
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    IV
    When in signal check mode, did you have the car in ACC (one power button push with foot off brake) or ON (two power button pushes with foot off brake)? Any lights on, heater blower, etc.?

    In my experience, comparing the MFD signal-check reading to readings of other ECUs, you can add about 0.6 V to what the MFD shows ... yielding about 11.2 in your case. Exactly how low that is depends in part on whether you had the car in ACC or ON. ON will pull the voltage down further than ACC will—how much more depending on what loads are turned on.

    For grins, I just walked out to mine (Gen 3 though), which has been sitting parked since early this evening. In ACC the MFD showed about 11 V. Switching to ON, it was pulled down to about 10 until the brake pump shut off, then bounced up to about 10.7. My hair isn't on fire to replace my battery.

    Have you had any issues that led to your concern?

    -Chap
     
  4. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    Three
    S46B24R is the buzzword for the correct battery.

    Last I checked, the Toyota dealer version had a 84 month (prorated0 warranty.

    amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=S46B24R