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2004 Prius Battery dies while Driving

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Shmeckledorf, Jul 1, 2020.

  1. Shmeckledorf

    Shmeckledorf Junior Member

    Joined:
    Jan 5, 2019
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    Location:
    Kansas City, MO
    Vehicle:
    2004 Prius
    Model:
    N/A
    Hello,
    Today I was driving on the highway in my 2004 Prius. I was going about 70 mph when the car would no longer accelerate when I pressed the gas pedal.The check engine light has been on and off for the past week or so, but my car has wiring issues, and this isn't uncommon. I ignored it, which turned out to be a mistake.

    I immediately put on my hazard lights and pulled over to the side of the road. The red exclamation light came on on the dashboard once I was stopped. The display is showing that I have a dead 12 volt battery. The thing is, I just replaced that battery with a brand new one about a month ago.

    I have full gas, and I just checked the oil yesterday and was at a good level. Does anyone know why my car would die like this while I was driving?
     
  2. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
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    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    The display isn't very accurate, best to use a voltmeter on the battery and then test again at the jumper points under the hood, drivers side.

    If you have warning lights on the dash, then you have OBD2 codes (DTCs) stored for retrieval.

    Many like using a hybrid compatible OBD2 code reader for faster diagnostics, and some even prefer a mini-vci cable and techstream.

    Do you have any OBD2 codes (DTCs) that you can share with us?

    Have you checked or replaced the inverter coolant pump lately?

    Does the AC still work when you're no longer able to accelerate?
     
  3. Shmeckledorf

    Shmeckledorf Junior Member

    Joined:
    Jan 5, 2019
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    0
    Location:
    Kansas City, MO
    Vehicle:
    2004 Prius
    Model:
    N/A
    I don't have any codes yet. I had to get it towed to the closest dealership and they're going to run a diagnostic in a couple of hours.

    The inverter coolant pump has never been replaced, and it hasn't been inspected in a while.

    Thele AC in my car was off when I had this problem, and I never attempted to turn it on when I pulled over.

    The dealership thinks the hybrid battery died, and if so, that means my car is totaled...
     
  4. dolj

    dolj Senior Member

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    May 14, 2012
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    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    Are the 12 V battery connections clean and securely fastened, including where the negative attaches to the body?
     
  5. sam spade 2

    sam spade 2 Senior Member

    Joined:
    Mar 31, 2018
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    Location:
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    Vehicle:
    2017 Prius c
    Model:
    Four
    NO, nobody knows for sure. How many dozen wild guesses would you like ??
    This is not a reasonable question to ask........but a LOT of people still do it.