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12v battery issues... again.

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Battery trouble., Jun 5, 2023.

  1. Battery trouble.

    Battery trouble. New Member

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    Location:
    Toronto
    Vehicle:
    2008 Prius
    Model:
    ----Canada----
    So 2998 Prius. Started having weird electrical screen issues and dead battery a few months ago. After reading a bunch of forums it became evident the 12v needed replacement. And some of the posts scared me into buying an oem battery from Toyota. Most expensive car battery I've ever had to buy, and I have a Porsche and a new large SUV's and pickups. So... I replaced the battery myself. Huge pain the a$$ for no good reason. Now, a month or two later went for a short drive this morning. Came home and car was dead again with weird electrical flickering on the screen. No light was left on. Beeping from perhaps low battery in fob? Either way. Any ideas? Most of the posts here say to buy a new battery. This is a new one!
     
  2. bisco

    bisco cookie crumbler

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    it sounds like you have a circuit that is draing the battery with the car off. you'll need measure the draw at the 12v with car off
     
  3. Battery trouble.

    Battery trouble. New Member

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    2008 Prius
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    ----Canada----
    Thanks for the response. So the battery is dead again. Can this measurement be taken on a dead battery or do I have to somehow try and charge it on a tender? I'm pretty handy, but don't know much about electrical stuff.
     
  4. SFO

    SFO Senior Member

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    Welcome to PriusChat!!

    After installing the new OEM 12v replacement, did you let the vehicle sit unused for 2 month?

    What measured voltage are you getting at the jump points under the front hood?

    If the battery now has low voltage, take it in for capacity test or to be recharged, they may even replace it. There shouldn't be a fee for such.

    FYI : you're moderated until you've posted 5 times.
     
  5. Battery trouble.

    Battery trouble. New Member

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    Location:
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    Vehicle:
    2008 Prius
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    ----Canada----
    No the vehicle has been driven almost every day. In fact, it was driven the day it lost power. I don't have any voltage meter tools but I'm going to get some and check. I'm less worried about the fees as the battery is brand new and under warranty and more concerned with the hugely annoying job of tearing the trunk apart and removing ductwork
    To change a battery! Sigh. Also, I'm sure they'll replace the battery but charge for the service. At least I've seen some places try that before. Anyways. Will check voltage and let you guys know.
     
  6. Tombukt2

    Tombukt2 Senior Member

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    You bought the battery from Toyota and replaced it yourself when you do this once or twice it becomes very quick the first time I took the battery 12 volt out of a Prius I thought to myself my god but. Just the one time now I can whip it out of there in about 8 minutes I can even get the hybrid battery out in about 45 maybe a tad less yeah there's a lot of trim and a lot of plastic and a lot of carpet looking stuff because that's what people like to see.