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Master warning flash on startup

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by EffinRed, Apr 22, 2012.

  1. EffinRed

    EffinRed Junior Member

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    Hello all -

    Details: 2009 Prius with Nav, no touring, cold battery voltage reading (via display) is 12.1v and 14.2v running

    I'm noticing something odd and I figured I'd ask and see if this is normal or something else. Sometimes on startup I see the red triangle then it goes away and sometimes it doesn't show up at all. I've had a few occasions where the car doesn't start. I usually shut the lights off and then it's OK.

    The car was just to the dealer for the 25k service and I told them about it, they couldn't find anything wrong. Am I chasing a ghost?
     
    #1 EffinRed, Apr 22, 2012
  2. nh7o

    nh7o Off grid since 1980

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    I'd say that >>50% of the troubleshooting posts here relate to 12v status. Definitely the lights and everything else should be off when you start.
     
    #2 nh7o, Apr 22, 2012
  3. EffinRed

    EffinRed Junior Member

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    The headlights?
     
    #3 EffinRed, Apr 22, 2012
  4. Britprius

    Britprius Senior Member

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    If you try to go to ready with the lights on you are already pulling 14to16amps from what appears to be a marginal battery at 12.1v standing this could bring the battery voltage down to below the point where the computers will not boot up or through errors. Remember things like the heater fan and brake pump could also be trying to run another 55/60amps.
     
    #4 Britprius, Apr 22, 2012
    1 person likes this.
  5. EffinRed

    EffinRed Junior Member

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    Interesting point. I did notice when I pumped the brake the battery dropped to 11.4v when the pump ran. So, is it time to replace the battery or should I wait until the fall?
     
    #5 EffinRed, Apr 22, 2012
  6. Britprius

    Britprius Senior Member

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    That really depends on if your prepared to gamble that it may let you down. I would change it now, but what are your driving habits how many hours or minutes do you drive each day.
     
    #6 Britprius, Apr 22, 2012
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