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forgot to turn off Prius for about 7 hours, concerns?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by benk33, Aug 4, 2015.

  1. benk33

    benk33 Junior Member

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    Hi all,

    I have a question. A friend of mine was taking care of my Prius while I was out of town (just to keep it being driven). When I got back, he told me that one day when he took it to work, he got out of work (around 7 or so hours later) and the security folks said that the car had been left on. It seems that he had forgotten to click the power switch off. The smartkey function was on and he had the key with him when he went into work. Should that have made it shut off? He said that he didn't leave air conditioning or lights on, and that when he got back there were three blue bars on the battery (I think).

    Anyone have experience with this? Why was the battery not depleted more? How bad is this? Any serious concerns for the battery?

    Thanks!
    Ben
     
  2. mmmodem

    mmmodem Senior Taste Tester

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    Absolutely nothing. Wasted some gas is all. Car and battery is designed to cycle on and off. Consider the car just traveled in severe traffic for 7 hours.

    You don't want the key to disable the engine instantly because if someone steals your car or a passenger walks off with the key, the car would block traffic or the driver suddenly loses control in traffic. Better to allow the car to be safely driven until it is shut off and parked.

    This is why I instruct everyone to never use the P button. Use the power button when leaving the car. Usig the power button auto parks. You can easily walk away from the car while parked and engine off. It's pretty hard to do that if you use the power button because the car will creep if you forget.
     
  3. valde3

    valde3 Senior Member

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    Or you can always lock the car. Prius can’t be locked from key button or from button on doors/trunk if it’s on.
     
  4. bisco

    bisco cookie crumbler

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    or make a habit of locking the doors. no harm, no foul. alls well that ends well.;)
     
  5. fotomoto

    fotomoto Senior Member

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    Some folks "camp" in the Prius overnight instead of getting a hotel room. My daughter and I sat for a couple of hours in ours with the a/c on during an +80f day and the ICE ran/charged the battery at roughly a 1 min on to 10 minutes off ratio.
     
  6. vskid3

    vskid3 Active Member

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    Yep, I've had mine on 12+ hours straight with the AC on, just lost a few MPG for the tank.

    As long as the car is in park, the engine will kick on as needed to keep the battery charged. The battery is usually kept in the 2-3 bar range when sitting like this. Just don't leave it in neutral and nothing bad should happen as long as you don't run out of gas.
     
  7. bisco

    bisco cookie crumbler

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    if you leave it on for 7 hours, with no accessories on, you won't burn much gas just keeping the computers and etc. running.
     
  8. GregP507

    GregP507 Senior Member

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    No harm done, but the doors were unlocked the whole time.
     
  9. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    There are stories about people using Priuses as auxillary power sources and leaving them on for days, so there is no concern about the car.

    Frankly, the only concerns you have with a parked Prius being left in the Ready mode are things like theft, fuel, carbon monoxide, fire (if parked in the grass,) etc.

    You can, and people do, walk away from the car having left it on......and it can be driven away like that....forever....until the power button is depressed and then you'll need the fob again.
    I've heard of spouses being dropped off at the airport and flying away with the fob in a pocket.
    Bummer.....

    It's all in the Owner's manual.
    Well.....not the airport part! ;)
     
  10. ftl

    ftl Explicator

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    I wonder what the record time for that is on PriusChat? Mine is 52 hours continuous running during Hurricane Sandy.
     
  11. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    It's probably as long as a Prius will take to suck a completely full tank down to completely empty...with the A/C off.

    I'm quite sure that somebody, somewhere left one running after topping it off and parking it.
     
  12. Kate Harvest

    Kate Harvest Member

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    No harm whatsoever to the car. The battery gauge on the MFD doesn't actually show the full charge range of the HV pack -- if I'm not mistaken 0 bars corresponds to 20% charge and full bars to 80%. The on-board computer generally won't let the pack's charge go below 40% (~ 2 bars) though... So leaving the car in Ready and the transmission in Park would mean that once the pack gets down to around 2 bars, the ICE would kick on for a minute or two every 10 minutes or so to put a little charge back into it. On the whole this would actually use very little gas and put very little wear on your engine.

    The one actual concern would be that with the doors unlocked someone could have gotten in and stolen some of your belongings... Or, if they were *really* smart, they could have stolen your HV pack itself, which does fetch a pretty penny.

    One nice consequence is that leaving the car in Ready for 7 full hours would mean your 12v aux battery was getting a constant 14v charging voltage the whole time, which would almost definitely bring it to a completely full state. :)