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Prime Charging when full

Discussion in 'Prime Plug-in Charging' started by ronus20, Sep 20, 2017.

  1. ronus20

    ronus20 Junior Member

    Joined:
    Sep 20, 2017
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    Location:
    San Jacinto, CA
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Hey everyone, first post, quick question regarding the charging. Ive tried searching and referred to page 133 in the owners manual but still couldnt find my answer. Please bare with me while I explain my scenario.

    I took delivery of my Prime Premium on Monday, but didn't get a chance to charge it until Tuesday night. Since I didn't get the Advanced trim where I could monitor the charging on the app, I tried to figure another way I could monitor remotely. The EV battery was completely discharged and I plugged it into a WeMo Insight switch and then plugged that into my electrical outlet as I was curious to see the actual amount of Wattage that was being used to charge. My thought was that I could monitor the WeMo app and when the wattage dropped on the charger, it was fully charged.

    I plugged it in and it was drawing an average of 1,435 Watts, the display in the car indicated 5 hour 30 minutes until fully charged. Fast forward that amount of time and I pull up the app again but it says it's still drawing about 860 Watts. I head out to the car, the 3 lights on the dash are all on and the display in the car says fully charged. So I'm thinking that maybe just having the charger plugged into the wall draws that amount of Wattage, but when I disconnect the charger from the car (while leaving the charger plugged into the wall) the wattage dipped to below 2 watts. So this tells me that even when the battery is fully charged but still plugged into the wall, it's still drawing 800+ Watts of power. Is this to maintain the power settings in the car (the miscellaneous stuff the car battery usually takes care of like clock, keyless entry, etc.)? Or is this still trying to charge the battery?

    Thanks!

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  2. Qmo

    Qmo Member

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    Other Non-Hybrid
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    N/A
    I noticed similar thing with my apartment's evGO chargers. Even when the car is fully charged, the indicator on evGo still shows charging. So not sure what the Prime is doing, I guess maybe the battery fan were still running?



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  3. Lee Jay

    Lee Jay Senior Member

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    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    No, you caught it at the wrong time.

    When it's fully charged the lights will go out. At that time, it will draw 2-3W. You must have caught it just at the moment it finished.
     
  4. ronus20

    ronus20 Junior Member

    Joined:
    Sep 20, 2017
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    Location:
    San Jacinto, CA
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    You are absolutely right. I think I went out a bit too son. My 2nd night of charge I decided to set the schedule to charge right before my departure @ 5:30am. Before I unplugged it in the morning the WeMo indicated less than 2 watts and the battery was fully charged. Chalk this up to my inexperience with the car. Hope to learn a lot more! Thanks buddy!

    Posted via the PriusChat mobile app.
     
  5. DavidA

    DavidA Prius owner since July 2009

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    Chicago western burbs
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    You'll just get used to it, and the time it takes. Lee is right about the LED's. They'll go dark when done. Also the little green light next to the charging handle will go dark. There is a slight delay of about a minute where the car is 100% fully charged and all those lights going out. I don't know what the car is doing in that minute.

    With my L2 home charger, anything around 5% charge left, or less, is always 2h 5m (not the 1:50 everyone says it takes). I don't have the Entune app, much less a smartphone, so I just look at the clock and go out there to unplug it. Don't really need an app to tell me it is done if the duration is always the same. That, and I can also look out the kitchen door and see the dash ;).
     
  6. GT4Prius

    GT4Prius Active Member

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    Location:
    Cumbria, UK
    Vehicle:
    2017 Prius Prime
    Model:
    Excel
    In v cold weather it may also use power after charging is complete, for the battery heater. And if fitted and set, the core climate cabin heater.

    Posted via the PriusChat mobile app.