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

What Triggers ICE

Discussion in 'Prime Technical Discussion' started by PiPLosAngeles, Dec 3, 2018.

  1. PiPLosAngeles

    PiPLosAngeles Senior Member

    Joined:
    Nov 18, 2012
    1,550
    720
    0
    Vehicle:
    2021 Prius Prime
    Model:
    LE
    Today I was driving in EV mode about 45 mph in traffic, climate control off, 94% SOC, outside temperature 50°F, and when I applied the brakes the ICE came on immediately and went through a 3-minute warming cycle. I realized then that I don't know what triggers the ICE in the Prime. In the PiP you could only trigger the ICE by turning on the heat, too much regeneration, or hard acceleration. None of those applied in this case, so that got me to wondering what are the known ICE triggers so I can try better to avoid them.
     
    priuscatprimeguy likes this.
  2. schja01

    schja01 One of very few in Chicagoland

    Joined:
    Apr 22, 2005
    1,765
    1,169
    0
    Location:
    Chicagoland
    Vehicle:
    2018 Prius
    Model:
    Prime Advanced
    If you totally avoid using the ICE for long enough period the Prime will take it upon itself to run it from time to time to keep things in good working order. Too lazy to look it up in the manual but there have been threads on this board about it.
    I want to say it happens every X number of months/miles but defer to someone more knowledgeable than myself.
    J
     
  3. PiPLosAngeles

    PiPLosAngeles Senior Member

    Joined:
    Nov 18, 2012
    1,550
    720
    0
    Vehicle:
    2021 Prius Prime
    Model:
    LE
    It had run the day before, but that's good to know in case of mysterious ICE starts. Now that you mention it, I don't think it had been on since they did some work on the auxiliary battery. Something might have been reset or who knows what.
     
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,132
    50,047
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    that is an odd one. every now and then, someone chimes in with a mystery ice start that no one can explain.

    prime was supposed to be the ev that pip never was, but it is still a bit of a mystery.

    some here swear that there engine has never started
     
  5. benagi

    benagi Active Member

    Joined:
    Jan 4, 2012
    525
    280
    4
    Location:
    Utah
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I wasn’t going to chime in but since someone brought it up again, I had an unexpected engine start a month ago. First time in 11 months of ownership . I know about all the do’s and dont’’s. Been following most all of the threads since I bought my car last Dec.

    Just Incase anyone is interested, here is what happened. Leaving for work as usual with a fully charged battery, I left the house on side streets, then get on the freeway about 2 miles from the house. Heading up the on ramp and starting to merge into traffic the ICE came on. Still don’t know why today. Hasn’t happened again.

    I do run my engine the last day of ever month. No heat or other accessories were on that day. Still a mystery but I’m really not worried about it. It’s been a great car, no real complaints. Enjoy and drive it.
     
    bisco likes this.
  6. schja01

    schja01 One of very few in Chicagoland

    Joined:
    Apr 22, 2005
    1,765
    1,169
    0
    Location:
    Chicagoland
    Vehicle:
    2018 Prius
    Model:
    Prime Advanced
    Did you inadvertently get into the "PWR" range while merging with traffic?
     
  7. PiPLosAngeles

    PiPLosAngeles Senior Member

    Joined:
    Nov 18, 2012
    1,550
    720
    0
    Vehicle:
    2021 Prius Prime
    Model:
    LE
    No, I was braking.
     
  8. benagi

    benagi Active Member

    Joined:
    Jan 4, 2012
    525
    280
    4
    Location:
    Utah
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Not that I was aware of. I usually keep an eye on the read outs on the mid.
     
  9. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,132
    50,047
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    does power band trigger ice like in the pip?
     
  10. Flaming

    Flaming Active Member

    Joined:
    Aug 9, 2017
    138
    122
    0
    Location:
    QC , Canada
    Vehicle:
    2017 Prius Prime
    Model:
    Technology
    Same thing happened to me .. 35 % battery left and braking to a stop sign .. engine turned on , Was like -5C outside
    same commute to work every day ... the only thing i can think off is maybe the battery was too cold and didnt like the regeneration so the engine turned to protect the battery .. IDK .. lol
     
    bisco likes this.
  11. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    10,985
    8,886
    0
    Location:
    New England
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Not related to the OP's case, but this will trigger ICE. 14F temp and a hard frost on the windshield.
    This will trigger ICE
    IMG_20181206_080039.jpg
     
    benagi and Mark57 like this.
  12. Mark57

    Mark57 2021 Tesla Model 3 LR AWD

    Joined:
    Aug 14, 2009
    2,945
    2,737
    0
    Location:
    OK
    Vehicle:
    Other Electric Vehicle
    Model:
    N/A
    Every time I read this subject, it makes me think we need a special group. Attendees would introduce themselves thusly . . .

    my name is xxxxx and I had unexpected engine start. :p
     
  13. PiPLosAngeles

    PiPLosAngeles Senior Member

    Joined:
    Nov 18, 2012
    1,550
    720
    0
    Vehicle:
    2021 Prius Prime
    Model:
    LE
    LOL. I wouldn't care if it wasn't for the warm up cycle that ensues. Knowing that it's using that gas for nothing because I'm never going to use the ICE after it warms up just burns me up when I'm trying to squeeze out the most efficiency possible. In the PiP I could pull over and turn the car off to stop the ICE. Restarting the car would revert back to EV mode. I haven't tried it in the Prime yet.
     
    bisco likes this.
  14. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,132
    50,047
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    should work
     
  15. priuscatprimeguy

    priuscatprimeguy Senior Member

    Joined:
    Nov 1, 2016
    2,730
    2,640
    0
    Location:
    Farmington Hills, Michigan
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    My name is ATHEIST prime and my ICE kicked in after driving 2.0 miles with 3.4 miles left of EV climate on eco at 70 f, never kicked in before this time, except when I fully charged the Battery and used cruise control, this time I was at a traffic light and proceeded to make a right turn

    Posted via the PriusChat mobile app.
     
  16. Roy2001

    Roy2001 Active Member

    Joined:
    Apr 1, 2009
    371
    158
    0
    Location:
    Sacramento, CA
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    One of the reason ICE on is full or nearly full battery. The other reason is slow charging rate during winter.

    I mentioned in another thread that for the 0.7 mile down hill, I used to get 1.2-1.3 miles of charge, now with 30-40F outside, I get only 0.7 mile of charge. So the rest 0.5 mile energy need to go somewhere, and ICE would be on almost every morning.
     
  17. PiPLosAngeles

    PiPLosAngeles Senior Member

    Joined:
    Nov 18, 2012
    1,550
    720
    0
    Vehicle:
    2021 Prius Prime
    Model:
    LE
    I was able to repeat the conditions. I would guess it has to do with some conservative assumptions and battery temperature. The ICE triggered in exactly the same spot under very similar conditions on another occasion. It seems that the battery is unwilling to accept more than a couple of second's worth of regen at 50°F, at least at 94% SOC.