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Which battery is the problem?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Laura1011, Feb 9, 2021.

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  1. Laura1011

    Laura1011 New Member

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    Vehicle:
    2012 Prius
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    Two
    My 2012 Prius won't start. I last drove it Friday evening, no problems or indication of issues. Monday morning, it won't start. We tried to jump start it from our other car, and it still won't start. Is there a way I can tell if it is the starter battery (cheap fix) or the hybrid system battery (expensive fix) that is the problem without paying to tow it to a repair shop and have them assess it?
     
  2. JC91006

    JC91006 Senior Member

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    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    Does your headlights turn on nice and bright? Radio and all the lights on the dash works properly? If not, then that's a good indication the 12v battery is dead and you'll need a new one. Also if that 12v battery is over 5 years old, chances are it would be dead and need a replacement.
     
  3. rjparker

    rjparker Tu Humilde Sirviente

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    Location:
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    Vehicle:
    2012 Prius v wagon
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    Three
    If someone has a voltmeter they can measure the 12v at the jump point. Below 11.7v its unlikely to initialize the computers. Sometimes you have to leave the jump on for at least five minutes to have a chance.

    Jump point gen3 Prius.JPG
     
    Steph1972 likes this.