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2010 good battery, car dead

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by ens, Jul 31, 2017.

  1. ens

    ens New Member

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    Car set overnight. Next morning it's completely dead. No lights, nothing. Checked battery at jumping post in fuse box and shows 12.89 volts. Any ideas?
     
  2. bisco

    bisco cookie crumbler

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    sounds like a blown fuse maybe. that voltage is fairly high, how old is the battery?
     
  3. ens

    ens New Member

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    Update....found out it was the 12v battery. Could jump start it and engine starts and runs for about 2 minutes then quits. Was going to drive it around to see if it would charge up the 12v, but engine wouldn't start up again. So was only using the Hybrid battery move. So is this a sign that the 12v battery needs a good charge or maybe replacement??? Any help greatly appreciated.
     
  4. ens

    ens New Member

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    Bought it a year ago. Has 120,000 miles. Will look to replace it. See my updated post. Thanks for responding.
    After I got it started, then shut it down. Battery showing 5.8 volts.
     
  5. bisco

    bisco cookie crumbler

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    still confusing. open the battery and check it there. if it's still 12.9, take it to an autoparts store for a load test. there is a date code on top. if it's over 5 years, just replace it.
     
  6. NavyLCDR

    NavyLCDR Active Member

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    Did you turn the car off in between? The engine starts from the main traction battery, not from the 12v battery. The 12v battery is only used to boot the computers to get into ready mode. Once the car is in Ready mode, the main traction battery takes over all loads and the 12v battery supplies nothing - it is only getting charged at that time.
     
  7. ens

    ens New Member

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    Battery was 5 yrs. old. Got a new one and everything seems to be fine. Thanks all for responses.
     
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  8. bisco

    bisco cookie crumbler

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    pleasure.