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ICE comes on anyway

Discussion in 'Prime Main Forum (2017-2022)' started by priuscatprimeguy, Feb 26, 2017.

  1. priuscatprimeguy

    priuscatprimeguy Senior Member

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    just for you @I want my PHEV I hope you're happy, because you have succeeded in messing up my perfect 999.9 MPG score:p
     
  2. bwilson4web

    bwilson4web BMW i3 and Model 3

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    We need to step back and ask if we have found an acceptable workaround?

    The original problem was intermittent and difficult to reproduce. Now I have high confidence that we've found enough to replicate this problem at will (or at least I can.) It is no longer a surprise but somewhat predictable. Happily, avoiding one of the triggering events can avoid the problem. My favorite is to turn cruise control ON before driving off.

    The effect of this symptom is not safety related but affects fuel economy in cool weather depending upon driving style. So instead of pegging tripmeters at 199.9 MPG, an unaware driver could get about 1/3-1/2 that MPG.

    The rarity of this problem is a curiosity which is what attracted me to it. But I also have other demands on my time and need to put this aside for now. We can pick it up later.

    GOOD LUCK!
    Bob Wilson
     
    #902 bwilson4web, Dec 9, 2017
    Last edited: Dec 9, 2017
  3. benagi

    benagi Active Member

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    Interesting story about the brake pause. The first time it happened to me it scared the hell out of me. Come to find out it was the abs system reacting to a couple of pot holes while exiting the freeway and braking hard just before the light at the end of the off ramp. I can make it do it every time now if I wanted but I don’t now that I am aware of that particular problem on the same off ramp I take everyday on the way home from work.
     
  4. Lee Jay

    Lee Jay Senior Member

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    Well, I accidentally tested this today. For some reason, my car didn't charge last night (I suspect my son didn't plug the connector all the way in until it locked). Anyway, the car was in a 53°F garage all night and the temperature outside was 33°F. I drove with the cruise on as always and the battery ran out on this particular hill. The ICE didn't kick on until 0.0 miles remaining.
     
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  5. VTBIGDOG

    VTBIGDOG Active Member

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    So today it happened to me...first time. Here are the details

    I am in SE Georgia...flat as a pancake,except for one suspension bridge with about a 7-8 degree rise and then subsequent drop. Rise is 1/4 mile, drop is the same. EV mode...had gone 10.2 miles, had 27.2 left. 54 degrees out. No wind. Heat, defrosters, heated seats all off. Low beam headlights on. Cruise was set to 45. I crested the top of the bridge and was descending the back side. Car was regenning but not excessively. The engine came on and stayed on for a warmup cycle, then went off and never came on again. I arrived at my destination, another 6 miles from that point. An hour later I retraced the same route with cruise on. ICE did not come on the entire way.

    I've come across that bridge with cruise on at 45 mph at least 50 times in the last 2 months without the ICE ever starting. I have no clue what happened, so I was looking for Rod Serling to see if I was in the Twilight Zone!
     
  6. bwilson4web

    bwilson4web BMW i3 and Model 3

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    There can be multiple, intermittent problems. Sad to say these can delay getting the primary one resolved.

    I appreciate the report and we’ll put it in the queue. As you’ve pointed out, it is not reproducible at will.

    Bob Wilson
     
  7. HPrimeAdvanced

    HPrimeAdvanced Senior Member

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    Could Mr. VTBIGDOG have reached the threshold of mileage where car ICE starts, in order to maintain the engine?

    .
     
  8. DavidA

    DavidA Prius owner since July 2009

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    Still, as far as we know, there isn't a mileage threshold. There might be a time threshold where the car thinks the gas is old enough, though hard to believe either would be tied to cruise control usage.
     
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  9. bwilson4web

    bwilson4web BMW i3 and Model 3

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    He didn't report it concurrent with cruise control operation but rather geographical or slope based. I can easily believe there is a secondary, slope triggered, event since that matches the first, 'reviewer' reported, engine ON event. It also matches the Colorado event. But first things first, let's get the intermittent problem we know 'run to ground' and then we can spend time looking at a slope based, event.

    Please understand this does not mean I doubt the slope events but rather, there may be more than one, intermittent problem ... until we find a way to make the second one come on at will.

    Bob Wilson
     
  10. HPrimeAdvanced

    HPrimeAdvanced Senior Member

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    Uncle Bob, I'm changing your name from "Bob" to "Job"!!

    .
     
  11. VTBIGDOG

    VTBIGDOG Active Member

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    One important factor in my scenario....the car was going downhill and in regen. I think that was also the case in other scenarios.
     
  12. VTBIGDOG

    VTBIGDOG Active Member

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    To answer the previous questions, i had made a trip of 190 miles the day before, 85 miles each way. I user all EV and then the ICE kicked in...normal operation. On the way home I added 5 gallons of fuel, then drove the remaining 40 miles home. It was the first fuel I had put into the car since October 16th.
     
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  13. VTBIGDOG

    VTBIGDOG Active Member

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    Same trip today, same parameters. Temperature 57F. No ICE.
     
  14. Salamander_King

    Salamander_King Senior Member

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    14F limit for EV is now confirmed. Last Friday, morning temp was 16F and ICE did not kick in during entire morning commute. This morning temp outside indicated by car was 10F. The car was outside fully charged and plugged in while climate prepping. No frost on windshield (=no defroster). Unplug charger, and get in a car to start the car. Initially when I put in Drive, it showed 22.3 mile EV range on EV mode, but moment after, EV indicator disappeared and ICE kicked in. I drove all 18 miles of commute on HV mode this morning, saving entire EV range for afternoon commute back home. Afternoon temp should be above 14F for me to use EV.

    IMG_20171218_062346.jpg IMG_20171218_062408 (1).jpg
     
  15. Lee Jay

    Lee Jay Senior Member

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    I did run it in Ev with heat on (no defrost) in 12F once and the engine did not kick in.
     
  16. Salamander_King

    Salamander_King Senior Member

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    I don't think 14F is precise automatic cut-off for EV. Last Friday, when the cars indicator was 16F to start, the temp dropped to 14F at some segment of my commute while driving on EV, ICE did not kick in during the time when the temp stayed at 14F.
     
  17. priuscatprimeguy

    priuscatprimeguy Senior Member

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    was your car outside and not in a garage? @Lee Jay?
     
  18. Lee Jay

    Lee Jay Senior Member

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    For about 3 hours.
     
  19. JamesBurke

    JamesBurke Senior Member

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    Heater turned on but below heatpump range so ICE came on to supply heat? or is this some minimum EV temp. Still have the battery warmer turned on? On by default says the manual.

    Ignored this thread for a year but now I have watched all of Cats vids. This DRCC thing is bizarre. Maybe a c/f unit conversion screw up in software?
     
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  20. Lee Jay

    Lee Jay Senior Member

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    The manual says the former.