Triangle of Death 2012 Prius 175,000 Miles

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Bbs20, Dec 10, 2024.

  1. Bbs20

    Bbs20 Junior Member

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    Hello everybody,

    I have been the proud owner of a 2012 Prius since August of 2021. I bought the car with about 130k miles on it and she now has about 175k. I was initially confused by the fact that the battery bar never completely filled but this forum reinforced my belief in the car, since then the car has been perfect! I've been diligent with care, being an "old" Toyota, especially with oil changes every 5,000 miles. In my area it was a challenge (?) to find somebody to do an oil change on a Prius but after that it was very consistent!

    Yesterday evening, I was leaving a family members house and immediately after the first stop sign (200m from their house), my dash lit up like a Christmas Tree, including the triangle of death and at least 4+ other lights. Reading Dr. Google wasn't helpful and honestly left me more confused. Before this incident the car's most recent trip was 48MPG at an average speed of about 60. Consistently during my commute, we average 39-44MPG going ~76+MPH. The most recent trip was less than two hours before the incident.

    Thankfully, I was able to limp her home, my dad has a code reader and a tool to measure battery voltage. We haven't tested anything due to the weather. I'm wondering if this sounds familiar to anybody or if anybody has any ideas? I'm hoping this isn't complete battery failure due to my cars previous stats. From what I've read online it could be 10+ issues, including issues a code reader couldn't pick up. I'll update with any knowledge receive! But any information will be greatly appreciated before a broke college student starts chasing rabbits.

    Please Give Me Hope!
     
  2. bisco

    bisco cookie crumbler

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    could be a million reasons. you will need a prius aware scanner to get the proper codes
     
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  3. Benjibabs

    Benjibabs Junior Member

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    I drive a 2012 Prius as well. If you did not get a message like "Hybrid system issue, Park the car in a safe place bla bla bla," it is probably NOT hybrid battery issue. What are the lights you have on? I I've seen traction, brake, ABS and another light lit up simultaneously. It has been on and off for me and still trying to figure it out.
     
  4. Bbs20

    Bbs20 Junior Member

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    Today's update is hopeful. We believe that my 12v battery is dying. It measured 11.5v initially and ~14v with the car running. Once it was unplugged and then plugged back in, it reset and started up while using the battery per usual(without all the extra warning lights), the battery was from 2016 and since we bought the car used we didn't realize its age. Thirsty minutes the car wouldn't start, we believe this is due to the 12v battery. Tomorrow we are picking up a new 12v battery and hoping that solves our problems. A (hopefully) cheap fix considering the $$$$ the car has saved me in gas.
     
  5. Grit

    Grit Senior Member

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    Looks like code reader is low priority, let’s chuck parts at it first.
     
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  6. ASRDogman

    ASRDogman Senior Member

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    Make sure you charge that battery for at least 6 hours to give it a full charge.
    They never charge those batteries, they just sit their and discharge over time.
    5 amps or less.
     
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  7. Brian1954

    Brian1954 Senior Member

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    Yes, you need to replace the 12v battery, but this will not keep the warning lights from coming back on until you determine what the problem is and fix it. You need to purchase a scan tool that can read all the trouble codes in a Prius. Read this thread: https://priuschat.com/index.php?posts/3290690
    The Autel AP200 is a very good choice and is presently on sale for $55.20 on Amazon. Buy it while you can get it.

    When warning lights are illuminated on the dash, that means there are trouble codes that need to be read. Determining the trouble code is the first step in the process of fixing the car.
     
    #7 Brian1954, Dec 11, 2024
    Last edited: Dec 11, 2024
  8. Mendel Leisk

    Mendel Leisk Witness Leader

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    With 11.5 volts, and the age, it’s replacement time. Do that first, and if all lights shut off, I’d dub it done.

    a brand new battery will charge up fine without intervention, just regular use of the car. That said, I would look into acquiring a smart charger.
     
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  9. ASRDogman

    ASRDogman Senior Member

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    UPDATE??? Did you get he 12v battery and install it? After you charged it up?