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EV Mode - Dropping Out of EV at 21 mph!

Discussion in 'Gen 3 Prius Main Forum' started by sbenbow, Aug 17, 2009.

  1. sbenbow

    sbenbow New Member

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    Hi All,

    I don't know if anyone else has been having problems with their EV mode on the New Prius? I got a Prius T4 11 days ago, and when I first had it the EV mode was fine (eg it enabled me to drive at up to 31mph on EV model only).

    There have been several instances over the last 3-4 days when I'm in EV mode that it drops me out when i reach 21mph. (this is when the "excesive speed" warning sign comes on). It is happening more and more regularly now, and i didn't know if anyone else had experienced it.

    I have checked to make sure that it's not because i'm accelerating too fast (the message also differs if it drops out because of excessive accelerataion rather than excessive speed) and i've also checked to make sure that there is enough "battery" for it to continue in EV mode.

    For example, today going downhill, no major acceleration, the speedo crept up to 21mph, and then the warning sign ("excessive speed") came on and it dropped out of EV mode. At the time i had "half" battery power left.

    Then, on my through town, I was able to quite happily do up to 30mph on EV mode (with more acceleration than example above) and it was almost down to a "quarter" battery. Couldn't figure out why it worked in one instance and not the next!!!

    I've been told that I will have to wait about 2 weeks before they (toyota garage) can look at it (as i need a courtesy car to replace it for the day and there aren't any available before then).

    Has anyone else experienced this, or found out what the problem was? Is there a "hack" or some kind of button press that may reset the factory settings?
     
  2. jay_man2

    jay_man2 jay_man_also

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    Several of us have reported dropping out of EV mode at 9-11 mph, but that appears to be related more to the car needing to get up to operating temp and some other parameters I read but don't recall off hand. The way it was explained made it seem like normal behavior. Maybe this is similar.
     
  3. Tideland Prius

    Tideland Prius Moderator of the North
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    Are they both with the EV button pressed or is 30mph done without the button pressed?
     
  4. sbenbow

    sbenbow New Member

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    They were both done with the EV button pressed (eg the little green EV light was "on" on the dashboard).
     
  5. Tideland Prius

    Tideland Prius Moderator of the North
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    Odd. (also it's interesting to note that your limit is 30mph whereas ours is 25. We switched places for the Gen III model).

    What about the engine. Is it fully warmed up compared to the time you only got up to 21mph?
     
  6. 3PriusMike

    3PriusMike Prius owner since 2000, Tesla M3 2018

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    In the US version there are two speed settings, 10 mph and 25 mph. When the car is cold (being warmed up or immediately after you push the power button and the ICE hasn't yet come on) you may not exceed 10 mph or EV mode will be cancelled. The 25 mph limit applies after the car is warm.

    I imagine you are experiencing these two limits.

    3PriusMike
     
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  7. SoonerJohnInDallas

    SoonerJohnInDallas New Member

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    This is rather disappointing that the car must be warmed up to get any reasonable use out of the EV mode. I live about 1/2 mile from my local grocery and a 7-11 and had hoped to be able to drive to/from them in EV mode as needed without the car being driven otherwise. (I did make it all the way to the grocery the other day in EV after I'd been running errands and just left again to go to the store, but it wouldn't even go into EV mode at all when I left the store to go back home.)

    Other than the seeming lack of usability as a full electric car, I *love* my new 2010 (level IV package in Silver/Ash) after a whole 4 days of ownership!
     
  8. dsviv

    dsviv Member

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    Today I put the car in ready, pressed EV and a window popped up reading "EV mode not available" The car had been sitting in a parking lot for 6 hours and had 6 bars. Any thoughts?
     
  9. cmalberto

    cmalberto New Member

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    Yeap - Thats what I get too. I think the the ICE has to warm up first. Wish it didn't have to. This would be cool to EV to the store and back.

    --Mickey
     
  10. sbenbow

    sbenbow New Member

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    Call me daft, but what is the ICE thing? And how can you tell if the car has warmed up? I can't seem to see any "temperature gauge" readings in the car.

    BTW - I still think the Prius is absolutely great!!! :)
     
  11. meannotgreen

    meannotgreen New Member

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    No. If you press EV almost immediately after pressing Power then you get EV mode and the ICE doesn't start even if it's cold. Handy for moving about the drive/garage (but probably no more than that).
     
  12. cmalberto

    cmalberto New Member

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    I gotta try this today when I leave for work here shortly. This sounds doable(and rememberable).

    --Mickey
     
  13. urlyadoptr

    urlyadoptr New Member

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    ICE = Internal Combustion Engine, which, when paired with an electric traction motor, creates a hybrid vehicle.
     
  14. pfoutty

    pfoutty New Member

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    R U saying that your Prius came with an EV mode switch and it was purchase in the US? I want to put one on my Prius and I was told that it will void the warranty in the US. Anyone know about that? Thanks Paul

     
  15. dsviv

    dsviv Member

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    Almost every time I use use the car I push the EV button to leave quietly. Don't read anything into that, I just think it's cool. Anyway, yesterday I went to the dealer to have them do a couple of customizations and now EV is no where to be found.

    Today when I left work I did the same thing at 6 bars. EV came on like normal and just like it should it kicked off at 12mph. But here's where it got weird; I drove about ½ mile to the post office and within that span of time, while using ICE, the bars dropped from 6 to 2 and remained there until I got home (about 1½ miles). the trip back to work (2 miles) and still 2 bars.

    I noticed low battery yesterday when I left the dealer, but figured they had been using the a/c or something. I had completely avoided using the remote a/c to retain what little battery I have. It probably wouldn't have worked anyway.

    I have had the car for almost 8 weeks and can only remember a handful of times that the bars were below 6. What happened?
     
  16. 3PriusMike

    3PriusMike Prius owner since 2000, Tesla M3 2018

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    This is true, but it should be noted that you also need to have the battery SOC at 4 bars or more. There may also be other conditions.

    I find this feature useful in that when driving out of my driveway in the morning or company parking lot at night it delays the ICE starting for 50 feet...or 500 feet. This reduces the amount of warmup time with the car moving very slowly and replaces it with warmup time with the car going faster. My theory is that this results in greater mpg overall.

    I am getting higher mpg than in my Gen I or Gen II, by at least 10 mpg so it might be a reason. But I have yet to get my second fillup (just a few days away) in my Gen III.

    3PriusMike
     
  17. 3PriusMike

    3PriusMike Prius owner since 2000, Tesla M3 2018

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    I see the battery SOC go down to 2 or 3 bars and back up to 6 bars all the time. A lot of this might depend on the length and speed of your commute and how much EV mode you get just before the end of your commute.

    In my case both to and from work I go the last 1/4 to 1/2 mile at 25 mph or less (~80% of the time) as traffic allows. This usually drops the battery SOC below 4 bars. But in the middle of my commute I am on a 50 mph road with few stops and the SOC is usually up at 6 bars.

    3PriusMike
     
  18. Tideland Prius

    Tideland Prius Moderator of the North
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    The Prius will use the battery when the engine's warming up. That is normal. That's why I usually accelerate lightly during the warm-up phase to preserve battery charge. True, you can use some since the engine will be idling so might as well recharge the battery but if you're not paying attention, it has no problems using up the battery while the engine is warming up. (At least that's the way it worked on the Gen 2. You'll accelerate but the engine rpm doesn't change. It stays at idle b/c the battery is propelling you)
     
  19. dsviv

    dsviv Member

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    why the sudden change after a visit to the dealer? Typically, the battery stayed around 6/7 bars. Now all of a sudden it rarely gets over 3. If it does get to 4 bars it almost immediately drops back down to 2 after only ICE use. I have had only limited use of EV mode & no use of the remote a/c.

    I had been using EV several times a day & remote a/c daily after leaving work in the afternoon. Now, I rarely have enough bars for EV and none for remote a/c. I haven't been able to use it in the past 3 days.

    The only thing I had done at the dealer was changing the remote from 2 clicks to 1 click to open all the doors and lowering the delay for headlights off from 60 seconds to 0 seconds. Now, as soon as I open the drivers door, the lights go out. My own version of auto-headlights.

    Neither of these changes should have made a difference to the battery charge, in fact, if anything the headlight change should have made it better.
     
  20. Tideland Prius

    Tideland Prius Moderator of the North
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    Yeah, they shouldn't change the way the battery performs.

    Btw, auto headlights do have a Follow-Me-Home function where they stay on for x seconds.