1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Gen 4 Prime (2020) not fully charging anymore

Discussion in 'Prime Care, Maintenance and Troubleshooting' started by hans1, Mar 28, 2024.

  1. hans1

    hans1 Member

    Joined:
    Oct 10, 2019
    53
    29
    0
    Location:
    USA
    Vehicle:
    2020 Prius PHV
    Model:
    XLE
    Couldn’t find any threads with the problem I’m seeing.

    My 2020 Prime at under 40k miles now only charges from empty 4.9 kWh (when at home, or at public chargers) and then stops. Car won’t allow charging any more than that. Up until the past few weeks, it used to charge 5.9 kWh from empty.

    In all the years, have never seen this before, for any temperature or weather.

    The estimated range is also down to 18-19 miles, from 21-22 miles.

    Any ideas?
     
    #1 hans1, Mar 28, 2024
    Last edited: Mar 28, 2024
  2. Mr.Vanvandenburg

    Mr.Vanvandenburg Senior Member

    Joined:
    Mar 15, 2007
    1,204
    435
    0
    Vehicle:
    2020 Prius Prime
    Model:
    Limited
    How do you measure the kwh? The estimated range does fluctuate on previous driving conditions. Maybe battery temp is a factor.
     
  3. hans1

    hans1 Member

    Joined:
    Oct 10, 2019
    53
    29
    0
    Location:
    USA
    Vehicle:
    2020 Prius PHV
    Model:
    XLE
    Oh, it was how many kWh that the ChargePoint app showed were added. And this was from battery being empty. This has happening every time, and only started over the past month.

    And at home, I’m seeing the same reduced range to go, after “fully charged”.

    Really a step change from everything previous over the past several years.

    Is there any way to reset the battery and charging? Almost seems like the car is confused?!

    p.s.- the thing I’m worried about is not really the range to go, but unable to accept a “full” kWh charge from empty
     
    #3 hans1, Mar 28, 2024
    Last edited: Mar 28, 2024
  4. route246

    route246 Member

    Joined:
    Jun 18, 2007
    97
    49
    0
    Location:
    SF Bay Area
    Vehicle:
    2020 Prius Prime
    Model:
    Limited
    What is your climate like? It sounds like it may be a battery state of charge capacity problem. Are you cycling frequently or leaving it fully charged for long periods of time?
     
  5. hans1

    hans1 Member

    Joined:
    Oct 10, 2019
    53
    29
    0
    Location:
    USA
    Vehicle:
    2020 Prius PHV
    Model:
    XLE
    Climate is mild, and no temperature extremes. Charge every day, and don’t leave fully charged more than a day or two at most. Drive most days.
     
  6. vvillovv

    vvillovv Senior Member

    Joined:
    Mar 19, 2013
    3,865
    1,329
    1
    Location:
    NY
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Do you use an app to monitor anything besides kW s into the hybrid battery
     
  7. sylvaing

    sylvaing Senior Member

    Joined:
    Jul 15, 2023
    1,180
    495
    0
    Location:
    Canada
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Base
    I'll sound like a broken record but Hybrid Assistant is great for that.
     
    vvillovv and hans1 like this.
  8. hans1

    hans1 Member

    Joined:
    Oct 10, 2019
    53
    29
    0
    Location:
    USA
    Vehicle:
    2020 Prius PHV
    Model:
    XLE
    Good thoughts all, thanks. Will have to look for that. I checked the miles/kWh from the display, and it looks like it has also slowly degraded over time, with the worst drop over the past month.
     
  9. hans1

    hans1 Member

    Joined:
    Oct 10, 2019
    53
    29
    0
    Location:
    USA
    Vehicle:
    2020 Prius PHV
    Model:
    XLE
    Found other threads about battery degradation, and that does look like what I’m getting.

    It seems like maybe all my driving in EV mode at high speed (75-85 mph on highways) does make a difference in more quickly degrading battery ability to fully charge?! Even with under 40k miles on my 2020 Prime.
     
    vvillovv likes this.
  10. Mr.Vanvandenburg

    Mr.Vanvandenburg Senior Member

    Joined:
    Mar 15, 2007
    1,204
    435
    0
    Vehicle:
    2020 Prius Prime
    Model:
    Limited
    There an eco diary which shows the daily and monthly miles/ kwh. That would show the efficiency changes. Maybe if you drive only ev around town for awhile and see if anything changes in the capacity. I don’t know why it would, because full ev’s drive highway not losing capacity. Or maybe they do. You do use the battery intensively for long periods going those speeds
     
    #10 Mr.Vanvandenburg, Mar 30, 2024
    Last edited: Mar 30, 2024
  11. vvillovv

    vvillovv Senior Member

    Joined:
    Mar 19, 2013
    3,865
    1,329
    1
    Location:
    NY
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    I didn't want to ask it, but I'm glad you said it. Those speeds in EV mode is gonna do in the tiny EV battery. It gets even worse when driving those speeds and running out of EV range and having the engine switch on cold. Even 100 F is cold for the engine at those speeds. A lot of owners have posted that is how they drive their Primes. :eek:
    It wouldn't be AS noticeable in the Gen 5 Prime as it will be in the Gen 4 Prime, and even more noticeable in the Gen 3 Plugin even though it's top EV speed was 64 mph if I'm remembering right.
    DrPrius and CarScanner are also useful apps.
     
    #11 vvillovv, Mar 30, 2024
    Last edited: Mar 30, 2024
  12. hans1

    hans1 Member

    Joined:
    Oct 10, 2019
    53
    29
    0
    Location:
    USA
    Vehicle:
    2020 Prius PHV
    Model:
    XLE
    Whoops. I drive right up to the about 85 mph limit just before the ICE comes up, whenever I can avoid it turning on. But do let up on the accelerator whenever transitioning out of EV mode, and try to keep it gentle then. Will see what the apps say.
     
    vvillovv likes this.
  13. sylvaing

    sylvaing Senior Member

    Joined:
    Jul 15, 2023
    1,180
    495
    0
    Location:
    Canada
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Base
    If I know I'll be needing the engine later on in my drive, I'll warm up the engine before going by turning the defrost on and off. It doesn't take long for the engine to warm up, if you still have your exhaust heat exchanger that is lol.
     
  14. hans1

    hans1 Member

    Joined:
    Oct 10, 2019
    53
    29
    0
    Location:
    USA
    Vehicle:
    2020 Prius PHV
    Model:
    XLE
    Looked at my monthly miles/kWh, and it has dropped from 4.2 kWh a year ago, and continued a steady decline to about 3.6 kWh now. And yes, I guess my high speed EV driving and acceleration has taken its toll.

    Spent a day of driving very conservatively mostly in the city, below the speed limit, and when no one was around at half the speed limit (!), and got it up to 4.5 kWh. But no way I’ll be driving like that long term, haha.
     
  15. iskoos

    iskoos Active Member

    Joined:
    Dec 24, 2017
    401
    246
    0
    Location:
    Orlando, FL
    Vehicle:
    2010 Prius
    Model:
    III
    I don't think Prime is meant to drive extensively on EV mode (especially at high speeds). Yes, it has an advertised 25-mile EV range, but it is still primarily a hybrid vehicle with much smaller battery compared to full EVs. My understanding is that you are driving your vehicle on EV whenever possible and charging it every day. This type of extensive use will cause battery degradation no doubt.
    Every time you power of your vehicle, it gives you an EV driving score based on 4 parameters. May I ask what score you typically see on your screen?
     
  16. hans1

    hans1 Member

    Joined:
    Oct 10, 2019
    53
    29
    0
    Location:
    USA
    Vehicle:
    2020 Prius PHV
    Model:
    XLE
    Too ashamed to say, and actually I don’t remember, maybe I might be putting it out of my mind
     
  17. iskoos

    iskoos Active Member

    Joined:
    Dec 24, 2017
    401
    246
    0
    Location:
    Orlando, FL
    Vehicle:
    2010 Prius
    Model:
    III
    I think I got my answer :)
     
  18. Peng Xiao

    Peng Xiao Junior Member

    Joined:
    Apr 12, 2019
    84
    13
    0
    Location:
    New Jersey
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    Some code reader can tell the battery capacity percentage, like BlueDriver. I got 86.3% on my 2018 PP when I tested in June 2023.
     
  19. jerrymildred

    jerrymildred Senior Member

    Joined:
    Oct 28, 2016
    11,518
    14,127
    0
    Location:
    Tampa, FL
    Vehicle:
    2017 Prius
    Model:
    Two
    Can we assume that the charger is stopping at 100% indicated? You never said. If it stops short of 100% that's a different matter.

    High speed EV driving will increase the wear on the battery for a couple reasons. One, the higher current is hard on it. Also, since you're using it up more quickly, you're probably increasing the cycle count and that's another wear factor.

    However, battery degradation is neither an indicator nor a cause of low mi/kWh except if it leads to more frequent charge/discharge cycles.

    Dr. Prius should tell you what's going on inside the mysterious aluminum box back there.
     
  20. sylvaing

    sylvaing Senior Member

    Joined:
    Jul 15, 2023
    1,180
    495
    0
    Location:
    Canada
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Base
    I wouldn't rely on Dr. Prius for a Prime. Email I got from them:

    I don’t think Dr. Prius App is fully calibrated for the 2017 Prime yet, we only have a chance to work on the Gen1 plug-in Prius, we need to find a test car and calibrate it, FYI.
     
    jerrymildred likes this.