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EV mode issue but engine runs

Discussion in 'Prime Care, Maintenance and Troubleshooting' started by lmans66, Oct 31, 2018.

  1. lmans66

    lmans66 Junior Member

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    Since we are moving into colder weather, this might just be natural but when I turn on the car and it goes to EV mode, I notice that ''a few times' the engine is running as well, as I can hear it. Also, as I drive, one time it was obvious that the engine was running as the gas mileage was moving down. Is this due to colder weather and just getting the car warmed up, or I have the defrost on or ?

    As an example, The other day I got in the car, EV showed on the dash,...the engine was heard running. It also happened sitting at a light and moving on when changed to green...in all cases it goes away. But the EV mode is on so it shouldn't happen at all, right?
     
  2. priuscatprimeguy

    priuscatprimeguy Senior Member

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    If you're using cruise control when temperatures are below 50 f then yes ICE will kick in otherwise it shouldn't kick in mlm

    Posted via the PriusChat mobile app.
     
  3. bisco

    bisco cookie crumbler

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    front defrost on = engine running in ev mode
     
  4. lmans66

    lmans66 Junior Member

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    You mean with defrost = ICE ? If EV, ..yes I can see that but that doesn't answer my question. Why would ICE come on in EV mode?
     
  5. bisco

    bisco cookie crumbler

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    I mean if you press the front defrost button while in ev mode, the engine will come on.

    There is a list of reasons in the o/m iirc plus the usual ‘and for reasons not listed here’ disclaimer
     
  6. priuscatprimeguy

    priuscatprimeguy Senior Member

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    Because the front defroster requires more heat than what the traction Battery can deliver

    Posted via the PriusChat mobile app.
     
  7. lmans66

    lmans66 Junior Member

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    Yes, that makes perfect sense....and more than likely since the defrost is what needs to come on some of these days.... thanks for the response, jim
     
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  8. john1701a

    john1701a Prius Guru

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    The button serves as an override, for when you need window clearing as fast as possible. When you don't, just stick with the blower option on the climate screen.