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Okay. Who HASN'T had a 12V battery issue with their 2023-24 Prime?

Discussion in 'Gen 5 Prius Main Forum' started by REBobBecker, Mar 30, 2024.

  1. GcinFl

    GcinFl New Member

    Joined:
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    Location:
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    Vehicle:
    2024 Prius
    Model:
    XLE
    What about those of us with non-Prime HEV models? My 12V drains quickly. After driving, it never charges to above 12.35. Then in 2 days of sitting it will be down to 12.06 or so. First scheduled maintenance will be in July. Hopefully they'll have a solution.
     
    bisco likes this.
  2. Maturedriver

    Maturedriver Junior Member

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    Location:
    England
    Vehicle:
    2024 Prius Prime
    Model:
    V
    Has your dealer installed a tracker?

     
    GcinFl likes this.
  3. Paul Gregory

    Paul Gregory Active Member

    Joined:
    Dec 9, 2022
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    Location:
    Alberta
    Vehicle:
    2024 Prius Prime
    Model:
    XSE
    I had some serious issues, but nothing since I installed a battery maintainer. I was unable to start the car once, while leaving it parked overnight at a hotel. Since then I've carried an extension cord and made sure to plug in the maintainer overnight.

    I also have an auxiliary battery, like on a camper. It fits nicely into the space near the left rear fender. It's connected to the main 12V battery through a VSR isolator, which prevents the auxiliary battery draining when parked. The Voltage Sensitive Relay (VSR) cuts in at 13.3 volts and cuts out at 12.8 volts to ensure the primary battery is always charged and ready to start the vehicle.

    If the auxiliary battery goes dead from running the drink cooler overnight, it only takes less than an hour to charge it up again through the isolator connection. I have also rigged a heavy duty bypass switch around the isolator, with a 30 amp fuse, in case I need to "boost" the primary battery. So far, the bypass current has never exceeded 10 amps.
     
    #123 Paul Gregory, Jun 23, 2024
    Last edited: Jun 23, 2024
  4. bisco

    bisco cookie crumbler

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    boston
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    Plug-in Base
    having to keep a maintainer on it is a real plug for toyota engineering
     
    GcinFl likes this.
  5. Jay Edelman

    Jay Edelman New Member

    Joined:
    Jul 13, 2023
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    Location:
    Monterey
    Vehicle:
    2023 Prius Prime
    Model:
    XSE
    I went on travel for exactly two weeks and when I returned from our flight the battery was too low to start the car. Unfortunately it never gave me a clear indication of why it wouldn't start, so I kept trying until the battery was well and truly dead. I find it very unreasonable that an otherwise regularly driven and maintained new car can't sit in a long-term parking lot for two weeks in moderate temperatures and humidity without draining completely. In my mind, that's a serious design or engineering flaw.
     
  6. Rafsdhc6

    Rafsdhc6 Junior Member

    Joined:
    Jun 27, 2023
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    Location:
    Ontario
    Vehicle:
    2023 Prius Prime
    Model:
    XSE
    Which point for the -negative connection did you end up using?