Gen 3 Replace Hybrid battery worth it?

Discussion in 'Gen 3 Prius Technical Discussion' started by Mabus, Nov 4, 2025.

  1. Mabus

    Mabus Junior Member

    Joined:
    Apr 7, 2024
    7
    3
    0
    Location:
    Sweden
    Vehicle:
    2009 Prius
    Model:
    N/A
    Recently I had a "Check Hybrid System" warning come on the dashboard of my 2010 Gen 3 Prius.
    After checking the trouble codes I got the trouble codes P0A80, C1259 and C1310 when reading with my OBD2 reader. I cleared the codes and they didn't come back until after a month. It always seems to happen when I drive at low speeds and braking very softly (could just be a coincidence?)

    I called my local Toyota workshop today and asked them what the issue would likely be and how much it would cost to fix it. According to them it's the hybrid battery that is starting to die and the only solution is to replace it.

    The car has rolled 180819 miles and according to the Toyota Workshop it will be really hard to sell the car with such high mileage and a faulty battery.

    So my options are now to either replace the battery or find someone who is willing to buy the car for parts.
    My question is: Is it worth replacing the hybrid battery on a Gen3 Prius with such high mileage? Is it normal for other faults to appear when the car reaches such high mileage?

    Price for a Toyota OEM brand new battery is 2090USD assuming I will take out the old one and put the new one in myself etc.
     
  2. PriusII&C

    PriusII&C Active Member

    Joined:
    Oct 15, 2013
    425
    142
    0
    Location:
    San Jose, California
    Vehicle:
    2012 Prius
    Model:
    II
    If the car is in good condition otherwise, I would probably replace the traction battery and keep driving it.

    If you are hands-on, you could DIY a grid-charger and recondition the traction battery. It will cost much less, probably $100 give or take.
     
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    113,850
    51,829
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    if you have the egr problems we do, and the pistons and rings issue, and the brake actuator issue, i wouldn't put any money into it.
    but you have to compare the repair to the cost of replacing it, and what you can afford.
     
  4. Mabus

    Mabus Junior Member

    Joined:
    Apr 7, 2024
    7
    3
    0
    Location:
    Sweden
    Vehicle:
    2009 Prius
    Model:
    N/A
    The car is otherwise in great condition. I service is according to Toyota specifications at a local workshop and the engine itself is in great condition.
    I have reconditioned the entire car inside and out to make it nice looking. Of course there are some things that show it's age but otherwise I think it's in a good condition for it's age and mileage.

    I read about the reconditioning the battery and might give that a try. Don't have any of the equipment for it at home but this weekend I will rip the battery out and see if I can find which cell is bad by doing some measurements.
    Do you know if replacing the cell and balancing the battery should be enough to get it to a good and running state? Or would a long time charge and discharge be needed?



    So far I have not had any EGR problems. The car runs good, the only issue right now is the battery and that it's consuming a bit more gas (which from my understanding is due to the battery not working as intended).
    However the EGR is something that I have had in mind and the plan is to rip it out and give it a good clean or replace it if it's in a really bad condition. As well as looking over the air intake.

    Otherwise there is no other issues with the car (that I know of).
     
  5. DirkAshburn

    DirkAshburn Member

    Joined:
    Apr 6, 2020
    143
    58
    1
    Location:
    Virginia
    Vehicle:
    2011 Prius
    Model:
    Four
    Check the market to see what other used Prius' are going for in your area with about the same mileage. If it's worth it, buy a cheap reconditioned battery for it then sell the car and buy something else. Last I looked a few months ago a reconditioned battery was $850 with a 3/yr warranty.
     
  6. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
    60,054
    41,288
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    That's not bad; that's with return of your "core" (the old one)?

    How's the oil consumption?

    Ever cleaned the EGR?

    How's it for rust?
     
  7. Mabus

    Mabus Junior Member

    Joined:
    Apr 7, 2024
    7
    3
    0
    Location:
    Sweden
    Vehicle:
    2009 Prius
    Model:
    N/A
    I would assume it's with return of my old battery. The guy I talked with did not specify but from my understanding that is somewhat the standard procedure when you purchase a whole new battery kit.

    The oil consumption is normal in the car. Not having any issues with it consuming a bunch of oil and I only use high quality brand oils in it.

    I have not cleaned the EGR yet but it's something that I have planned doing this winter. I have not had any of the known symptoms of a bad EGR. But figured I might as well clean it just to be safe and clean the intake manifold while I'm at it.

    So far there is no visible rust on the car. The paint job is nice looking on it except for the few damages like stone chipping and a mark where someone hit the car with their door.
    I clean the car regularly and make sure that during the winter I get rid of any salt that might have attached itself to the car. Engine bay looks great and nothing has been ruined by rust so far.
     
  8. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
    60,054
    41,288
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    With 181k miles, EGR cleaning is long overdue. The "EGR problems" and "bad EGR" will likely manifest as blown head gasket, soon. I know, it's not in the maintenance schedule: Toyota is sitting on this mess.
     
  9. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    113,850
    51,829
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    idk anything about battery reconditioning, but there are a lot of threads here if you search.
     
  10. Mabus

    Mabus Junior Member

    Joined:
    Apr 7, 2024
    7
    3
    0
    Location:
    Sweden
    Vehicle:
    2009 Prius
    Model:
    N/A
    I have ordered gaskets for the EGR and inlet manifold. Will take them out and clean them out next weekend.
    Also spoke with Toyota about the battery. And if I purchase a new one I won't have to hand in my old one so I could just sell it used to someone who wants to refurbish it.

    Took the battery out today and picked it apart. First obvious thing was that the nuts were very corroded. I took all of them off and cleaned the busbar brackets on both sides.
    No corrosion has traveled up the wires and caused any damage.
    Will install the battery tomorrow and hope for no more trouble codes.

    [​IMG]

    [​IMG]

    Not a huge difference between any of the cells when I measured them. Removed the busbar and had the cells completely disconnected from one another when doing the measurement.
    +------+------+
    | Cell | Volt |
    +------+------+
    | 1 | 8.09 |
    | 2 | 8.12 |
    | 3 | 8.12 |
    | 4 | 8.12 |
    | 5 | 8.12 |
    | 6 | 8.11 |
    | 7 | 8.12 |
    | 8 | 8.15 |
    | 9 | 8.14 |
    | 10 | 8.13 |
    | 11 | 8.10 |
    | 12 | 8.11 |
    | 13 | 8.12 |
    | 14 | 8.13 |
    | 15 | 8.11 |
    | 16 | 8.10 |
    | 17 | 8.11 |
    | 18 | 8.11 |
    | 19 | 8.13 |
    | 20 | 8.14 |
    | 21 | 8.12 |
    | 22 | 8.12 |
    | 23 | 8.09 |
    | 24 | 8.10 |
    | 25 | 8.13 |
    | 26 | 8.11 |
    | 27 | 8.11 |
    | 28 | 8.10 |
    +------+------+
     
    Mendel Leisk and bisco like this.
  11. indel

    indel Junior Member

    Joined:
    Apr 1, 2024
    39
    17
    0
    Location:
    Northwest Indiana
    Vehicle:
    2012 Prius
    Model:
    Two
    Are you absolutely sure about this? List price for gen 3 battery is $2588.67 plus a core charge of $1300 or so (see below for a quote I obtained last week from my local dealership).



    While there is a great amount of variability in battery prices among dealers (I was quoted by another dealer in SC for $1900 + core), I highly doubt they will let go of the core for free.

    Second, did you use any tutorials for cleaning and checking battery voltages. If so, can you link them?
     
  12. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
    60,054
    41,288
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Just curious what you mean by that.

    A purchase involving a "core charge", amounts to this:

    You pay a highish initial price, and the bill of sale promises that if you give them your old battery in decent physical shape (minus the bits that need to be transferred over), they will refund some of the initial price.

    12 volt battery purchases are often similar: bring them your old battery and get $20 refunded.
     
  13. indel

    indel Junior Member

    Joined:
    Apr 1, 2024
    39
    17
    0
    Location:
    Northwest Indiana
    Vehicle:
    2012 Prius
    Model:
    Two
    #13 indel, Nov 18, 2025 at 12:05 PM
    Last edited: Nov 18, 2025 at 12:46 PM
    Mendel Leisk likes this.
  14. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    7,533
    3,892
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    You have leaking blocks..... That is not good....
     
  15. Brian1954

    Brian1954 Senior Member

    Joined:
    Jan 31, 2021
    2,135
    827
    0
    Location:
    South Central PA, USA
    Vehicle:
    2011 Prius
    Model:
    III
    You are correct in the USA.

    The OP (Mabus) is located in the country of Sweden. The Toyota dealerships in that country appear to not require a return of the old HV battery, so there is no core charge added to the price of a new HV battery in Sweden.
     
    indel likes this.
  16. indel

    indel Junior Member

    Joined:
    Apr 1, 2024
    39
    17
    0
    Location:
    Northwest Indiana
    Vehicle:
    2012 Prius
    Model:
    Two
    Okay, yeah that makes sense.
     
  17. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
    60,054
    41,288
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring