1. Attachments are working again! Check out this thread for more details and to report any other bugs.

EV mode not predictable

Discussion in 'Gen 3 Prius Technical Discussion' started by rrolff, Oct 26, 2009.

  1. rrolff

    rrolff Prius Surgeon

    Joined:
    Aug 19, 2009
    1,610
    246
    0
    Location:
    So Cal
    Vehicle:
    2010 Prius
    Model:
    III
    I keep finding weird spots where in theory, I should be in EV, but the car won't let me, or it gives a strange message.

    The latest today - in almost stopped traffic (dropping off for school), at 10MPH, and coasting down a hill at that speed (not even getting faster), no foot on gas, I get something to the tune of "EV inactivated due to excessive acceleration". I know the car was feeling the standard 9.8m/sq sec due to gravity - but the car is always under that constraint (at least at sea level).

    I should start keeping a log (???).

    Am I the only one???
     
    1 person likes this.
  2. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,075
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    Perhaps a Valium would fix the problem. ;)

    Tom
     
    1 person likes this.
  3. ken1784

    ken1784 SuperMID designer

    Joined:
    Dec 18, 2003
    2,943
    1,378
    67
    Location:
    Yokohama, JAPAN
    Vehicle:
    2010 Prius
    Model:
    N/A
    The max EV speed is 10mph when the coolant temperature is below 70C(158F).

    Ken@Japan
     
    2 people like this.
  4. rrolff

    rrolff Prius Surgeon

    Joined:
    Aug 19, 2009
    1,610
    246
    0
    Location:
    So Cal
    Vehicle:
    2010 Prius
    Model:
    III
    Thanks - but it was running 10mph for a bit before giving the message - which has nothing to do with coolant (acceleration)...
     
    1 person likes this.
  5. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,075
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    There are a number of parameters that feed into the EV calculation. Without access to Toyota documentation, we can only speculate and infer what they are. You can try to map out all of the permutations, or you can just shrug your shoulders and accept that it is what it is.

    Tom
     
    1 person likes this.
  6. rrolff

    rrolff Prius Surgeon

    Joined:
    Aug 19, 2009
    1,610
    246
    0
    Location:
    So Cal
    Vehicle:
    2010 Prius
    Model:
    III
    Hrmm - I'll pass on the shrugging, and work at getting an answer... While 42 may work for some - I'm looking for more :rolleyes:
     
    1 person likes this.
  7. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,075
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    The Prius does offer a lot of mysteries to solve. It's like a rolling puzzle. That said, I'm pretty sure the answer *is* 42.

    Tom
     
    1 person likes this.
  8. patsparks

    patsparks An Aussie perspective

    Joined:
    Jul 12, 2007
    10,664
    567
    0
    Location:
    Adelaide South Australia
    Vehicle:
    2004 Prius
    Model:
    N/A
    Don't think about it so hard. Just drive it. Personally I let the system decide when to use EV, it is pretty good at it actually.

    Things that kick you out of EV are, coolant temp, battery charge, battery temp and the right foot.
     
    1 person likes this.
  9. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    45,024
    16,242
    41
    Location:
    Canada
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Have you ever considered that the engine cools down when you're not using it?
     
    1 person likes this.
  10. rrolff

    rrolff Prius Surgeon

    Joined:
    Aug 19, 2009
    1,610
    246
    0
    Location:
    So Cal
    Vehicle:
    2010 Prius
    Model:
    III
    To all the above, the simple answers move from:
    1. A message like "too much acceleration" when I am not accelerating, or moving more than 10mph, with foot off the gas for seconds, and no real perceived forward acceleration (I could feel the downward one - as I was firmly placed in my seat) - shows either an issue with software, or an issue with a sensor on my car.

    2. The number 42 should only be an issue with dolphins or people waiting at a diner - not for someone trying to find the answer to the Prius.

    3. Why do we take EV mode like it is some weird crazy alien animal that should be ignored - and not understood?????
     
    1 person likes this.
  11. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    45,024
    16,242
    41
    Location:
    Canada
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    There was a reason why EV Drive Mode was introduced into the U.S. later and not in 2004. Now I can see why.

    Also the fact that it's more aggressive than the Gen 2 doesn't help. I like my Gen 2 EV Drive Mode better.
     
    1 person likes this.
  12. rrolff

    rrolff Prius Surgeon

    Joined:
    Aug 19, 2009
    1,610
    246
    0
    Location:
    So Cal
    Vehicle:
    2010 Prius
    Model:
    III
    There are probably bugs, and a great opportunity for aftermarket "EV" add on to fix "bugs"...
     
    1 person likes this.
  13. ken1784

    ken1784 SuperMID designer

    Joined:
    Dec 18, 2003
    2,943
    1,378
    67
    Location:
    Yokohama, JAPAN
    Vehicle:
    2010 Prius
    Model:
    N/A
    My bad... I stand corrected.
    Is that symptom reproducible?

    If yes, would you please explain more detail conditions so that everybody can see the symptom?

    Ken@Japan
     
    1 person likes this.
  14. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,075
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    The Gen II Prius has its share of odd error messages, some of which seem unrelated to the actual cause. This Gen III "acceleration" message may be another one of these. I suspect Microsoft writes the error messages for Toyota.

    The message in this situation should read "42 - your dolphin is asleep."

    Tom
     
  15. Welshdog

    Welshdog Member

    Joined:
    Jul 11, 2008
    181
    38
    0
    Location:
    Austin, TX
    Vehicle:
    2010 Prius
    Model:
    IV
    Lately we have been getting this message from the Prius: "EV Mode Currently Not Available". The only thing I can see that has changed from earlier in the year is the ambient temperature is lower. Typically this message appears upon startup when the car has not been used in several hours and it is fully cooled down. Push the EV Mode button under these conditions and up pops the message. Unfortunately starting the car at night or early in the morning is when we want EV mode the most - annoying.
     
  16. going red baby!

    going red baby! still a n00b

    Joined:
    Jul 21, 2009
    610
    96
    0
    Location:
    Los Angeles
    Vehicle:
    2010 Prius
    Model:
    III
    I can sometimes put my car into EV mode right when I start it up and sometimes not and then I get that same not available message. So is this because of the weather/temperature? I'd really like to be able to use it when I just have to move the car across the street or something like that.
     
  17. Strangelove

    Strangelove New Member

    Joined:
    Nov 28, 2009
    15
    3
    0
    Location:
    Washington, Pa
    Vehicle:
    2010 Prius
    Model:
    II
    I'm a noob, but the whole EV thing has me nonplussed. I've played with it in my neighborhood on the way home. If I use EV I get bumped out due to excessive speed or acceleration and the ICE kicks in. If I just drive gently in normal or power mode the ICE stays off and I can run silently.

    Makes me wonder if EV isn't just a "gee-golly" button with little practical function.
     
  18. Rokeby

    Rokeby Member

    Joined:
    Jan 21, 2008
    3,033
    708
    75
    Location:
    Ballamer, Merlin
    Vehicle:
    2008 Prius
  19. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    45,024
    16,242
    41
    Location:
    Canada
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Except that EV Drive Mode is setup a little differently in the Gen 3 and definitely more restrictive (cold startup is one. Unless it's something like > 15°C outside, I can never start up in EV Drive Mode. It'll always say EV Mode not Available).

    Frankly, ECO mode works well as a substitute for EV Drive Mode because if the engine's off, you're in EV mode up to the middle bar (i.e. if you're in Hybrid ECO Mode) and frankly I don't accelerate hard in EV mode anyway so I don't need the full bar that EV Drive Mode provides.
     
  20. rrolff

    rrolff Prius Surgeon

    Joined:
    Aug 19, 2009
    1,610
    246
    0
    Location:
    So Cal
    Vehicle:
    2010 Prius
    Model:
    III
    As some astute EV savant (wish I had the name to give credit) pointed out - you can always get to EV - you just have to turn on the car, then put it in gear, then quickly press "EV". This works to 10MPH on a cold car. Once the car is hot, you can run EV to 25MPH - except:
    When the battery gets or is too hot
    When you accelerate too fast
    When you exceed 25MPH
    When you are driving on the 2nd Saturday of a leap year
    When on the 4th Wednesday of a month with a blue moon
    In any year that the Minnesota Vikings win a championship (this could trigger a recall)...
     
    2 people like this.