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Confused: Why does estimated EV miles keep dropping?

Discussion in 'Gen 1 Prius Plug-in 2012-2015' started by Den Hare, Oct 29, 2012.

  1. usbseawolf2000

    usbseawolf2000 HSD PhD

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    Neutral will not start the ICE if you go above 62 mph. It will overspeed MG1 and can damage it.

    If you glide in D, ICE will start up automatically.

    Either you want ICE on or not, the power demand at high speed is more suitable for the ICE. So it is best to stay under 62 mph if ICE is not needed, especially downhill.
     
  2. Jeffrey Perlman

    Jeffrey Perlman Junior Member

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    The same thing has happened to me. There's a screen that shows how much power you have instead of how many miles to go. That's an accurate indicator of what battery power you have.
     
  3. jdk2

    jdk2 Active Member

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    What screen is that?
     
  4. priuskitty

    priuskitty PIP FAN

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    Maybe he has a Scan Guage that show's SOC?:whistle:
     
  5. jdk2

    jdk2 Active Member

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    Or Torque. I haven't seen any native gauge on mine that shows power remaining except on the SGII and that's SOC as you noted.
     
  6. priuskitty

    priuskitty PIP FAN

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    my point xactly
     
  7. drash

    drash Senior Member

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    Or he might be looking at the battery level on the energy monitor or HSI which is a crude approximate of how much battery power is remaining.
     
  8. bisco

    bisco cookie crumbler

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    what screen is that? all i have is the battery with ev miles remaining estimate.
     
  9. priuskitty

    priuskitty PIP FAN

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    Above the EV miles indicator the battery icon?

    SGH-M919 ?
     
  10. Potorap

    Potorap Active Member

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    USB,

    Thanks for the reminder.
    Den, welcome to prius chat and the best purchase of an automobile. I agree with all about driving habits, my Pip did the same thing and I had same thoughts (something is wrong with this car). I stared with 16.8 went down to 11.9 at its lowest point and now I am daily 24.8 because I changed my driving habits. Stay focused on mpg and you will be fine. Welcome .
     
  11. drash

    drash Senior Member

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    Yes and yes. On the energy monitor the battery icon is a little more separated from the EV miles remaining and might appear as a separate entry.


    iPad ? HD
     
  12. Chris_SoCal

    Chris_SoCal Junior Member

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    The EV miles estimate is useless and varies wildly depending on your driving habits from one week to the next.
    They should have made it indicate battery %age, aka state of charge. I wish they would issue a firmware update to make EV miles/ SOC a switchable display. I think they could do it with the available graphics display.
     
  13. john1701a

    john1701a Prius Guru

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    % presented in a numeric form doesn't actually tell you much. Get an aftermarket gauge, you can see that for yourself.

    Toyota provided % in analog for instead. That makes seeing relative capacity available pretty easy. They even provided a finer scale for when you get close to the depletion point.

    Switchable could be nice, but it counters the KISS principle they've been using for Prius since 1997. Notice how only 1 motor/generator is displayed on the screen even though there are actually 2 ?
     
  14. kaiotes

    kaiotes Junior Member

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    my EV range range has refused to go up. I used to get about low 12.x when the temp was in the 50s and closer to 13 in the 60s. it's been pretty warm in san jose the last couple weeks, my range has dropped to high 11x and low 12s.
    seriously wrong!
     
  15. bisco

    bisco cookie crumbler

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    you 're probably only getting that many ev miles.
     
  16. Lourun

    Lourun Member

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    My was 12.3 in the summer bottomed out at 9.0, in the last week I have raised it up to 9.2 even in this polar vortex that we are have by driving as slow as I can, traffic this week locally has been unusually light, giving me an opportunity to drive like I'm 90years old.
     
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  17. 3PriusMike

    3PriusMike Prius owner since 2000, Tesla M3 2018

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    A lot of that is, IMO, because the algorithm they are using isn't very good. Here is an example. About 5-6 weeks ago I got a new 12v battery and my EV-estimate went to 13.5. Over a few weeks it settled in to 12.3 miles and didn't vary by more than 0.1 on any given day for weeks with my normal driving pattern. Then I went on a hike last weekend...drove in EV to the bottom of a hill switched to HV to go up the hill with ~1 mile remaining, went hiking for the day, drove back down the hill in EV and regen'ed to ~10 miles, then drove home using only 2-3 miles. Did some more errands to near zero EV. The next day the estimate was 12.9 miles. This week, back to my normal driving and 8-10 charges later the estimate still is at 12.8-12.9 and the weather has been colder and rainy as well.

    Bottom line...that "one" EV trip that got me ~30 miles on a charge should not still be skewing my estimate after all those charges and normal EV range like it has. The algorithm has to be some kind of moving average or weighted moving average. Based on these numbers it appears to be using about 30 full charges worth of trips for the calculation. I think it would do better to use fewer charges, but then throw out the high and the low of the charges not in the most recent 5 or 10. In the way you'd see a boost or drop from a one-time anomaly, but then soon after any anomalies would disappear.

    Mike
     
  18. Woolf

    Woolf New Member

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    I just purchased a used 2012 Prius Plug-In and noticed that I only ever see 9.5 miles for the range after a full charge. Thanks to those on this thread for explaining it to me. I'm not at all new to owning a Prius, as I originally purchased a 2001 model back when hybrids first hit the market. But the plug-in part of the car is definitely a new concept to me.
     
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  19. bisco

    bisco cookie crumbler

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    funny how some people post and never return.(n)
     
  20. Prius 2007 user

    Prius 2007 user Junior Member

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    From my experience with various cars, not only hybrids, mileage estimates are no more than ballpark figures, and pretty pessimistic ones at that. I regularly end up beating them by a fair amount. They only get accurate when you're nearing the limit, meaning if it tells you there's 10 miles worth of gas left in your tank, well that's pretty much it and you'd better fill up or else...

    My guess is that your actual EV mileage will remain more or less stable, regardless what the indicator says at the start of your trip. Try resetting the trip meter and make a note when the ICE kicks in ; I'm pretty sure you'll get very much the same mileage, day in, day out, and that it will be substantially more than your initial reading.

    I wouldn't worry about battery failure : A French motoring magazine ran a Prius reliability test involving about 20,000 cars, there wasn't a single instance of battery failure reported. That's how reliable they are, needless to say the Prius (all models considered) came up head and shoulders above the rest, including German cars.