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12v battery dead

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Sebpercu, Jul 30, 2021.

  1. Sebpercu

    Sebpercu Junior Member

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    My 12v is dead, 4v this morning after 3 weeks holidays... battery was already capricious before that and refused to start the car mostly when i was driving small distances> I tried to charged but the "smart" chargeur doesn't want to do it and put itself in security, so i imagine my battery is definitely dead.

    I saw few post talking about an Ebay battery at 100$, 12 Volt (12V) 55 Amp (55Ah) VRLA AGM Sealed Lead Acid Battery 55 AMPS HIGH CAP
    Any informations about it ? looks likes it need so adjustments to install. any advices ?

    thank you!
     
  2. rjparker

    rjparker Tu Humilde Sirviente

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    Most of us go for reliability and want an agm that fits with proper terminals and has a vent port. Both of which will be missing with the wheelchair battery. You can get one that fits with an aftermarket auto supply equivalent that might last 3 years or a Toyota oem battery that will last 7 years. Try negotiating with the dealer's part dept, not the service advisor by asking for a discount.
     
  3. bisco

    bisco cookie crumbler

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    i have read about some desulfating chargers that will bring your 12v back to life. check you tube
     
  4. Another

    Another Senior Member

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    how old is your battery? Sounds like it’s got some miles on it. I’m assuming it’s not under any sort of prorated warranty. You can easily check date code on battery. so my advice is bite the bullet, buy a new one and live in peace a few more years. If any warranty months left there may be some money in it. Some are out to 72 months new.
     
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    @Sebpercu : if you know, how old is your battery?

    BTW: "AGM" (Absorbent Glass Mat) batteries main feature is that they are much less prone to vent noxious gasses. I believe that's the main reason Toyota went with that style of battery. Also, if the you're in a collision, hit from behind, there's much less risk of spilled battery acid.
     
  6. Sebpercu

    Sebpercu Junior Member

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    The battery looks very old, 7v after regeneration and charge. Checked the date code and it looks like it was from 2015 (the 5 is scratched, so i think it is 2015 and not 2005 lol)


     
  7. Sebpercu

    Sebpercu Junior Member

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    Mine is doing it, but didn't work this time. I will have to buy a new battery unfortunately
     
    bisco likes this.
  8. SFO

    SFO Senior Member

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    The smart charger doesn't like low voltage, best to find a old school dumb charger and bring the battery up to 10V+, then switch over.
     
  9. sam spade 2

    sam spade 2 Senior Member

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    While that is true, it is HIGHLY likely that it won't hold a charge even after it appears to be fully charged.
    That might be a good plan IF your objective is to get it started once.......so you can drive it to a battery store !!
    :)
     
  10. sam spade 2

    sam spade 2 Senior Member

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    BUT......that is mostly just marketing hype and any positive results will be short lived.
    AND......it won't work at all if sulfating is not the original problem.
     
  11. bisco

    bisco cookie crumbler

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    i saw it on youtube, it must work
     
  12. Mendel Leisk

    Mendel Leisk Senior Member

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    A battery of dubious age, currently reading 7 volts, that a smart charger won't stoop to charge? It's time.

     
  13. Another

    Another Senior Member

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    Get a new Toyota OEM battery and get on with life. Many dealers have sales on them periodically. Check dealer websites for service specials.
     
  14. Another

    Another Senior Member

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