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Prime may start ICE in EV mode if Windshield Defogger switched on

Discussion in 'Prime Technical Discussion' started by GT4Prius, Nov 6, 2016.

  1. Lee Jay

    Lee Jay Senior Member

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    Then that's optimal for the Prime.

    It will start despite being in Ev mode when:

    • State of charge is low and you ask for near full-throttle.
    • Every 200km (200 miles?) to keep things lubricated, etc.
    • When you turn on the front defroster.
    • When you ask for heat and it's below 14F/-10C outside.
    That's all pretty rare stuff for most people.
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    Just to clarify: there are two "radiators" in a car's cabin ventilation system. One's got engine coolant, the other's got the AC fluid. They can work independently, or in tandem.
     
  3. GT4Prius

    GT4Prius Active Member

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    Thanks again.

    We use the front demister quite a lot here in the humid UK Lake District in our Gen2. In fact for most journeys except in the summer when the ac is in cooling mode. Maybe cabin preheat would help us to need this less, I don't know.

    Posted via the PriusChat mobile app.
     
  4. Lee Jay

    Lee Jay Senior Member

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    Okay, regarding the front defroster.

    There are two ways to do it. You can put it on heat and direct the heat to the forward windshield vents, or you can hit defrost mode. The engine only needs to start in the later case. The defrost mode will also dehumidify the air by running the heat pump in cooling (air conditioning) mode. To get heat in such a case, you need warm engine coolant so the engine needs to be running.

    If you don't need dehumidification, which you probably won't if you preheat (because no one is in the car breathing and thus adding humidity), then just forward heat may do the job.

    You can also switch back and forth between heat and A/C from the heat pump without starting the engine.
     
  5. Tideland Prius

    Tideland Prius Moderator of the North
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    Yeah it's 200 miles / 300 kilometres.
     
  6. Lee Jay

    Lee Jay Senior Member

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    I couldn't find it in a Toyota document. Do you have a reference?
     
  7. Tideland Prius

    Tideland Prius Moderator of the North
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    I spoke to the assistant chief engineer in NY.
     
  8. GT4Prius

    GT4Prius Active Member

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    Thanks. Switching is a new idea to me for this and sounds like a good one. Maybe one that Toyota could take up and implement as an automated ECO Demist setting on a future model.

    Posted via the PriusChat mobile app.
     
  9. priuscatprimeguy

    priuscatprimeguy Senior Member

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    Well, I was looking for the thread where ICE comes on even with climate off, front and rear defroster off and outside temperature is 46 F and EVSE was plugged in to utilize battery warmer function. I started out going 25 MPH for about 3/4 mile then gently accelerated to 35 MPH and BOOM! ICE kicked in, what gives? Checked how many miles since last time ICE kicked in it was 88.3 miles so it's not the 200 mile, ICE kick in interval.:eek::confused:
     
  10. Lee Jay

    Lee Jay Senior Member

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    Emphasis mine:

    EV driving may be canceled automatically in the following circumstances:
    ●When vehicle speed is more than approximately 84 mph (135 km/h).
    ●When power is needed temporarily, for example when the accelerator pedal is depressed firmly or when accelerating suddenly.*
    ●When the temperature of the hybrid system is high.
    The vehicle has been left in the sun, driven on a hill, driven at high speeds, etc.
    ●When the temperature of the hybrid system is low.
    ●When the heater is switched on when the outside temperature is below
    about 14°F (-10°C).
    ●When the windshield defogger switch is pressed. (→P. 491, 501)
    ●When the system determines that the gasoline engine needs to be started.
    The gasoline engine may also operate in circumstances other than those
    listed above, depending on conditions.

    *: When traveling in the EV auto mode only
     
  11. priuscatprimeguy

    priuscatprimeguy Senior Member

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    None of the above applied to me:mad: except for the battery warming feature, my battery was not warm enough.
     
    #51 priuscatprimeguy, Jan 17, 2017
    Last edited: Jan 17, 2017
  12. Lee Jay

    Lee Jay Senior Member

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    Of course it did - look at the bold text.
     
    priuscatprimeguy likes this.
  13. priuscatprimeguy

    priuscatprimeguy Senior Member

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    Yup, I edited my response before you quoted me:p
     
  14. Lee Jay

    Lee Jay Senior Member

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    There's a catch-all:

    "The gasoline engine may also operate in circumstances other than those listed above, depending on conditions."
     
  15. bisco

    bisco cookie crumbler

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    i test drove one today. they had it warmed up when i got there, but when i put in ev mode, every time i gave it a little gas, the engine would come on. we couldn't figure it out.

    my pip doesn't do that.
     
  16. Lee Jay

    Lee Jay Senior Member

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    Was the battery near dead?
     
  17. bisco

    bisco cookie crumbler

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    2 miles of ev left.
     
  18. Lee Jay

    Lee Jay Senior Member

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    So, it did that to me as well but only at pretty high throttle settings.

    I don't think two-motor usage is possible when the battery is nearly drained so it'll start doing that near the end of the Ev range at high throttle settings.
     
  19. bisco

    bisco cookie crumbler

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    that's probably it, but i'm a granny on the pedal. the pip doesn't do it. plus i was in eco mode which desensitizes the pedal. i would have to drive it again.
     
  20. giora

    giora Senior Member

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    Worth trying EV auto in this circumstance. I think EV auto does not use dual motors mode.