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

Does the Prius ECU learn your driving habits?

Discussion in 'Gen 2 Prius Main Forum' started by ZC1, Jun 11, 2008.

  1. ZC1

    ZC1 Junior Prius Owner

    Joined:
    Apr 18, 2008
    711
    13
    0
    Location:
    Metro Detroit
    Vehicle:
    2008 Prius
    It's a real question... brought on by some salesman who told me the Prius learns your driving habits and runs accordingly.

    According to what I was told, If you drive like a Grandma, the Electronic Control Unit (or one of the other 13 computers) learns your habit and then gives appropriate performance.
    But if you drive like Mario Andretti, the Prius is programmed for heavy acceleration and gives better accelerating performance.

    From a technical standpoint, I can see this happening because the ECU would merely record various operating and control parameters, store the parameter values in a table and after repeated uses, remap them as normal accelerating parameters for this car, trying to give the driver what he/she wants.
    (This is not fact, unless someone can confirm it.)

    Or is the Prius like a standard computerized car, which takes in various variables and quickly decides the output it needs and make the adjustment on the fly. No ongoing parameter tables necessary?

    Anyone?

    ZC1
     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,199
    6,464
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    If this is true, this is an undocumented feature. I have not been able to find mention of this in the 2004 New Car Features Manual or the tech training documents.
     
  3. penbed

    penbed New Member

    Joined:
    May 8, 2008
    222
    3
    0
    Location:
    USA-Arkansas
    Vehicle:
    2008 Prius
    Drive by wire...
     
  4. Jiipa

    Jiipa MGySgt USMC (Ret)

    Joined:
    Feb 23, 2008
    314
    2
    0
    Location:
    Oahu, Hawaii
    Vehicle:
    2008 Prius
    My wife and I must really have our Prius confused then because I try to wring out as many mpgs as possible a she has a lead foot.
     
  5. racerbob

    racerbob Member

    Joined:
    Mar 16, 2008
    138
    6
    0
    Location:
    S Florida
    Vehicle:
    2008 Prius
    Nope, no training by use of accelerator, brakes, or steering. Normal automatics in ICE powered cars will change transmission shifting baselines according to driver input. This is the only "learned behavior" that the user can control. This is evident when performing an TCM or ECM reset or disconnecting the battery. Prius doesn't have any trans shifts, so no learned control. The ECU will adapt to wear and vacuum leaks, to keep the engine running smoothly as it ages. Disconnect the battery on a 100k domestic car and see how poorly it will run when cold. It will take 10 miles or so and a few starts to relearn proper fuel trim.
     
  6. patsparks

    patsparks An Aussie perspective

    Joined:
    Jul 12, 2007
    10,664
    567
    0
    Location:
    Adelaide South Australia
    Vehicle:
    2004 Prius
    Model:
    N/A
    It learns what you want from the engine instantly, put your foot to the floor on the loud pedal and it learns you want to accelerate hard, press gently on the right pedal and it learns you want to accelerate slow.

    Mine seems to have learnt it is near home after it goes up the hill at 80km/h because once I get to the top of the hill and the battery it all topped up it hardly runs the engine from there to my home.
     
  7. racerbob

    racerbob Member

    Joined:
    Mar 16, 2008
    138
    6
    0
    Location:
    S Florida
    Vehicle:
    2008 Prius
    Just like a good horse. :D
     
  8. Rokeby

    Rokeby Member

    Joined:
    Jan 21, 2008
    3,033
    708
    75
    Location:
    Ballamer, Merlin
    Vehicle:
    2008 Prius
    ZC1,

    your question is very similar to one I posted a while back. The postings here
    are essentially parallel to those I got, with the possible exception being that
    the earlier responses were more detailed.

    As I see it, the Prius doesn't really "learn," it does record a whole lot of stuff
    for possible later use when conditions warrant.

    Here's the earlier thread:

    http://priuschat.com/forums/prius-technical-discussion/45271-how-what-does-prius-cpu-s-learn.html

    Don't be mistaken, I haven't the slightest idea what a "fuel map" is.

    Enjoy!
     
  9. CTitanic

    CTitanic Member

    Joined:
    Jan 23, 2011
    153
    21
    0
    Location:
    South Florida, FL, US
    Vehicle:
    2013 Prius
    Model:
    Three
    Sounds like science fiction. I haven't found anywhere any evidence of technology being applied in a Prius. Is it possible? From the technical point of view it's possible. For example, Microsoft handwriting recognition feature is capable of learning from your handwriting but if multiple users are using the same profile instead of an improvement in the recognition process you will get exactly the contrary. And that's the scenario that already somebody described here in this thread. In very few occasions our Prius are driven by just one driver so to implement such technology in it we need profiles/accounts and I don't see this anywhere in my Prius or any other Prius yet.
     
  10. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    338
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
    There are reports of people seeing a decrease in mpg's after the disconnection of the 12V battery, which after some time, will return back to normal. So there is a learning which happens over maybe a couple of hours or less. But not much is known about it. I think the learning is more about fuel type, ambient conditions, and best emissions control, as a guess.
     
    uart likes this.
  11. CTitanic

    CTitanic Member

    Joined:
    Jan 23, 2011
    153
    21
    0
    Location:
    South Florida, FL, US
    Vehicle:
    2013 Prius
    Model:
    Three
    It would be more realistic to say that the reported calculated MPG value is lower and after few hours, once the historical values is gathered the calculated values get more realistic. That's all.
     
  12. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,777
    48,983
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    why did we dredge this up?
     
  13. joeman

    joeman Member

    Joined:
    Aug 22, 2009
    239
    13
    0
    Location:
    Raleigh, N.C.
    Vehicle:
    2006 Prius
    Model:
    Two
    I agree, was over my head.

    Think this says it all, thanks Pat
     
  14. uart

    uart Senior Member

    Joined:
    Sep 7, 2009
    4,215
    1,200
    0
    Location:
    Australia
    Vehicle:
    2005 Prius
    No not a couple of hours, it was more like a month in my case. I think mine needed several full tanks of petrol before the displayed MPG reached it's final accuracy.
     
  15. Data Daedalus

    Data Daedalus Senior Member

    Joined:
    Jul 6, 2013
    1,022
    1,182
    0
    Location:
    Wembley, London
    Vehicle:
    2008 Prius
    Model:
    II
    How about the rumour that the Prius Navigation was capable of learning your repeat directional preferences (oh alright - preferred routes) after repeatedly trying to force you down it's chosen routes? Is that another Prius II myth? ;-)
     
  16. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,912
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    I've found that if you ignore her instructions for a few turns she does the typical female thing, and does not speak to you for a hour.

    John (Britprius)
     
    Data Daedalus likes this.
  17. Data Daedalus

    Data Daedalus Senior Member

    Joined:
    Jul 6, 2013
    1,022
    1,182
    0
    Location:
    Wembley, London
    Vehicle:
    2008 Prius
    Model:
    II
    Hahahahaha!! Sounds familiar :)