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ICE Starts in EV Mode with 6 miles left on Traction BAttery

Discussion in 'Prime Main Forum (2017-2022)' started by renoblueprius, Dec 4, 2020.

  1. renoblueprius

    renoblueprius Junior Member

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    I have been driving my 2021 PP XLE for about two months and am very satisfied.

    I have noticed 2 times now that the ICE has started in EV Mode with between 6 and 14 miles left on the Traction Battery. The outside temperature is around 48 deg F. It has happened after returning from a hike. The last 2 miles of the drive home is a 2 mile mild downgrade so the battery is charging most of the way. The ICE starts near the end of the downgrade.

    Is this normal?
     
    #1 renoblueprius, Dec 4, 2020
  2. schja01

    schja01 One of very few in Chicagoland

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    Mine did the same thing with 20+ miles left on the traction battery. That was 3 days ago. Temp was in the low 40’s. A mystery.
    EV
    Eco heat
    Eco drive mode
    No defrost
    It’s as if the car felt it needed to warm up the ICE. Lasted less than 5 minutes.
     
    #2 schja01, Dec 4, 2020
  3. Db17

    Db17 Member

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    The computer knows best ;)
     
    #3 Db17, Dec 4, 2020
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  4. Diemaster

    Diemaster Active Member

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    simple.......if you dont want the ICE to start just unplug the injectors. sure you'll get a christmas tree- lit dash but no gas will be used. :p
     
    #4 Diemaster, Dec 4, 2020
  5. Tideland Prius

    Tideland Prius Moderator of the North
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    Were you using B mode during that 2-mile downhill?
     
    #5 Tideland Prius, Dec 4, 2020
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  6. renoblueprius

    renoblueprius Junior Member

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    Yes I was in B Mode for the last mile
     
    #6 renoblueprius, Dec 5, 2020
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  7. AldoON

    AldoON Member

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    There is a downhill shortly after leaving work. In the summer I never had a problem with the ice kicking in while in B mode.
    The other day it was around 0 C and the ice kicked in on the hill. Now I avoid B mode and use light brakes. So far been good for no ice.

    I charge at work so my battery is at 98-100 percent going down the hill.
     
    #7 AldoON, Dec 5, 2020
  8. Gokhan

    Gokhan Senior Member

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    In other words the state of charge (SOC) of the traction battery drops to 0% when there is still a lot of estimated EV range left.

    Of course, this is normal. The estimated range is a guess only. You need to keep an eye on the SOC. You can see the SOC if you switch to the eco gauge on the multifunction display (MFD).
     
    #8 Gokhan, Dec 6, 2020
  9. Tideland Prius

    Tideland Prius Moderator of the North
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    I have noticed when it's cool (cool, not cold.. so yeah 50°F is about right), shifting into B for regen instead of using the brake pedal sometimes kicks the engine on. It did that to me once on a short, but steep hill. I thought "oh, I'll just go into B down this hill to maintain speed instead of riding the brake pedal" and it kicked the engine on instead.

    However, the difference is that mine is a steeper hill and you said yours was a mild or gentle one.
     
    #9 Tideland Prius, Dec 6, 2020
  10. schja01

    schja01 One of very few in Chicagoland

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    Fwiw in my case no B Mode. The ICE “just started, warmed up and shut down” for no apparent reason. I have been driving less due to COVID so perhaps it thought it was time to exercise the ICE?
     
    #10 schja01, Dec 6, 2020
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  11. AldoON

    AldoON Member

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    In my case I was on a steep hill too.
     
    #11 AldoON, Dec 6, 2020
  12. Trollbait

    Trollbait It's a D&D thing

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    That could be likely. A PHEV can't go indefinitely on EV alone; problems will start coming up with an engine that is never exercised.

    I believe other PHEVs would give a message about that being a case though.
     
    #12 Trollbait, Dec 6, 2020
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