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

P0A80 after "B" mode

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by pixiemag, Jul 30, 2024.

  1. pixiemag

    pixiemag New Member

    Joined:
    Jul 30, 2024
    2
    1
    0
    Location:
    Orange County, CA
    Vehicle:
    2012 Prius
    Model:
    II
    Recently a red triangle appeared on our car's dashboard - it happened after my husband used "B" mode for a short time. I checked codes using Car Scanner and that's what we got:

    P0A80
    Hybrid battery pack Deterioration

    P0517
    Battery temperature sensor - circuit high

    First thing we did was checking hybrid cooling fan if it's not dirty or clogged - it was pretty clean and it looks like it works well. After that, codes disappeared but after a few days P0A80 came back (this time none of us used "B" mode).

    A few months ago we replaced a battery for a refurbished one from a place that seemed to be a good one in our area. We replaced it because a red triangle appeared, and the mechanic told us we need to replace it. What's funny, it happened right after my husband used "B" mode.

    So yesterday I run a test using Dr Prius and it looks like we need a new battery soon (this time we're doing a new one). It looks like the battery doesn't have much capacity left (I did this test twice and got a very similar result), delta soc is high and block #1 is always the tallest on a diagram (I don't know if that even matters now).

    But I wonder, why both times when my husband used "B" mode for a very short time, we got battery issues? Do you have any idea if there's anything else that may causing battery issues and P0A80 code? Or is it's just weird coincidence that he used that mode twice, and each time red triangle appeared? I just want to avoid a situation when we buy a new battery, but next time one of us uses "B" mode, something happens to the battery again.
     
  2. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

    Joined:
    May 12, 2018
    7,427
    6,913
    1
    Location:
    Pennsylvania
    Vehicle:
    2018 Prius c
    Model:
    Two
    I think you just discovered the difference between 'seems good' and 'is good.'

    Weird coincidence. Lots of people need to use B mode frequently, especially in hills and mountains. If anything it is more gentle on the battery.
     
    Brian1954 likes this.
  3. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,369
    1,791
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    I like most things when it's time to get a battery for your TV remote you go to the CVS and you get new duracells You don't put the old ones in the fridge or try to put them on a hobby charger or put them in the oven for a few minutes or or or or you get new ones because you want to be watching TV tonight probably pretty much same with your hybrid electric vehicle and by the time several people play with hobby chargers and all kinds of this kind of thing probably would have just been smart to get a new battery and be done with it and have your 8 to 10 years of well driving without issue for the most part or you do things like this every 2 years and pay 12 to 1,300. Funny thing is for 300 more dollars or so you could have had a brand new battery from Panasonic
     
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,132
    50,047
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    how many miles on your car?
    b mode increases charging rate which can be prolematic in a battery with old reconditioned cells.
    hopefully under warranty by the 'seemed to be a good one' company, but if not, consider a new oem battery.
     
  5. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,904
    16,213
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    ^^^ This. If there's a causal connection, it more likely had to do with the circumstances that prompted DH to use B mode in the first place, usually a situation where the regen in D would have been even harder on the battery. B is meant to be the right choice for those situations, and if the battery is that marginal, the light would probably have come on even sooner in that same situation if B had not been used.
     
  6. pixiemag

    pixiemag New Member

    Joined:
    Jul 30, 2024
    2
    1
    0
    Location:
    Orange County, CA
    Vehicle:
    2012 Prius
    Model:
    II
    Yes. The place has been recommended in local forums/groups but now I don't trust them that much anymore.

    about 170k. Unfortunately not under warranty anymore, the red triangle appeared shortly after we reached the mileage limit that was covered by the warranty. This time we consider to order a new battery and before doing that, I wanted to check if using "B" mode could cause the problem or if it was just a coincidence.
     
    bisco likes this.
  7. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

    Joined:
    May 12, 2018
    7,427
    6,913
    1
    Location:
    Pennsylvania
    Vehicle:
    2018 Prius c
    Model:
    Two
    You've got that exactly backwards.

    B mode tells the hybrid system to charge the battery slowly and gently, because there's still a lot more hill to descend. So it dumps more energy into spinning the engine instead.
     
    Brian1954 likes this.
  8. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,132
    50,047
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    ah, thanks. then what other reason for b mode causing the problem several times?
     
  9. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

    Joined:
    May 12, 2018
    7,427
    6,913
    1
    Location:
    Pennsylvania
    Vehicle:
    2018 Prius c
    Model:
    Two
    That's exactly the point: B mode didn't cause this problem. It was a coincidence.
     
    bisco and Brian1954 like this.