Could this be something other than 12- volt battery?

Discussion in 'Prius c Care, Maintenance and Troubleshooting' started by LadyB, Feb 10, 2025.

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  1. LadyB

    LadyB Junior Member

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    Howdy.

    Last week my 2014 Prius C developed an intermittent starting issue.

    Sometimes you get in, push start and it would not start... sometimes some clicking noises. (so far waiting a few and re-pressing power started vehicle.)

    I got to know I would NOT have issue if dash showed keys present symbol when I got in.

    Vehicle signal check: (pushing power 2x, car button, flash lights 3x) showed: Battery 12.1 v after a 15 minute drive. While driving it went up to around 15 +- 0.2.
    (2 weeks prior headlamp replaced w/proper # bulb.. not sure if could be related, but thought I'd mention.)

    Is this definitely, a "replace your 12 volt battery issue", or could it be something else, before I drop $300 on a new battery?

    Followup question: what settings do I lose when 12v gets disconnected and how to prevent if it wipes Gps?

    Many thanks!
    Ber
     
    #1 LadyB, Feb 10, 2025
  2. Brian1954

    Brian1954 Senior Member

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    How old is the 12v battery?

    If the 12v battery is the original one, it is time to replace it.
     
    #2 Brian1954, Feb 10, 2025
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  3. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    I can't give you a concrete diagnosis through a website, but it sure does sound like the 12v battery is done for.

    For a 2014 the correct battery should be the SB3420R, which is around $250 at the Usual Suspect friendly local auto part stores.
     
    #3 Leadfoot J. McCoalroller, Feb 10, 2025
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  4. vvillovv

    vvillovv Senior Member

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    I might have suggested to try a float charger / trickle charger for like $10 at harbor freight. Simple tool, clip it on red + black - for a day.
    if it's a 10 year old battery it's most likely kaput. But you wouldn't know for sure without charging it first.

    You can also use the same tool to keep your settings while installing the new battery. As you are removing the terminals from the old battery, get it half way off, than clip on the red to + . Repeat for the black - terminal .
    Install new battery, check you setting.

    CEN-TECH 12V Automatic Battery Maintainer $9.99
     
    #4 vvillovv, Feb 10, 2025
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  5. LadyB

    LadyB Junior Member

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    Thank you, all.

    I priced the battery and the local Toyota Parts had it for $252, which surprisingly beat the chain price on that Die Hard. Huge surprise as their service dept is a major rip off!

    I have a trickle charger from when my son and I did open-heart surgery on my old gen 2's hybrid battery years ago! I will have to see if I can find it. (spoiler alert: the patient lived for another 25,000 + miles.} The old thread is still on this site!

    What do I lose if I don't find/hook up trickle charger?
     
    #5 LadyB, Feb 10, 2025
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  6. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    I wish I could tell you in full detail, but yours is older-enough, and a different trim level.

    Ours seems to need the driver's window run up and down a couple of times after a full 12v blackout. I believe the maintenance reminder countdown stays good, but I can't swear to it.
     
    #6 Leadfoot J. McCoalroller, Feb 10, 2025
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  7. BiomedO1

    BiomedO1 Senior Member

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    You should hook up that trickle charger under the hood jump points.
    Use a rag or cut up a pool noodle to cover the positive cable connection - once it's off the battery. That way if it flops around, you won't accidentally short anything.

    Hope this helps.....
     
    #7 BiomedO1, Feb 10, 2025
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