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2010 prius won't start after running out of gas

Discussion in 'Gen 3 Prius Main Forum' started by David Lang, Aug 26, 2024.

  1. SPlautz

    SPlautz Junior Member

    Joined:
    Oct 24, 2009
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    Location:
    Virginia Beach VA
    Vehicle:
    2010 Prius
    Model:
    V
    Thought I'd give my opinion since I've been through some of this with my Prius. A few years after getting my car, I ran out of gas a couple miles from the gas station I was trying to get to. How I knew it was out of gas was that I couldn't go faster. It seemed I could only maintain current speed and when I slowed down, the battery wouldn't speed it back up. Eventually I had to pull off to the side and stop. A police officer helped get a gallon of gas to put in it, but it still wouldn't start. After calling roadside service, they put in 2 more gallons, which finally made it start. Hearing all the horror stories in here about burnt out fuel pumps and drained HV batteries, it sounds like I dodged a bullet and luckily I stopped it when I did.

    Also, last year, my nine year old 12v battery died after not driving the car for almost a month. At first the engine started just fine, but after about 30 seconds, the engine stopped and everything started lighting up like a christmas tree on the dash. The engine would not start again after that. Operating the door locks sounded noticeably weaker so I knew it was the 12v battery. The HV battery had charge in it, and the 12v battery at least still had some voltage, enough to barely operate the locks and light up the dash. So I question the notion that the HV battery actually cranks the engine. If it did, my engine would have started. And sure enough, as soon as I replaced the 12v battery, the engine started right up! And the guy who says a Prius can't be jumped must not read manuals. It clearly states in the Prius manual how to jump the car, like any other car, to start the engine. Why would they put that in the manual if it was the HV battery cranking the engine?!?
     
    #41 SPlautz, Sep 5, 2024 at 5:42 AM
    Last edited: Sep 5, 2024 at 5:48 AM
  2. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
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    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    The 12v battery powers the computers that tell the computer that all is well with
    the computer and you can ready the hybrid system. If the 12v battery is low/weak, the
    computers can't start correctly and the hybrid system will not be able to start.
    Jumping with a good battery gives the computer what it needs to ready the hybrid system.

     
  3. MAX2

    MAX2 Member

    Joined:
    Aug 12, 2024
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    Location:
    Third Rock from the Sun
    Vehicle:
    2007 Prius
    Model:
    N/A
    Pull the orange high voltage battery disconnect and try to start the engine from 12V with a new charged battery.
    Post a video of you starting the engine. Ok?