Further hybrid system testing and help needed.

Discussion in 'Gen 3 Prius Main Forum' started by Prius92, Jun 28, 2025.

Page 2 of 2
  1. Prius92

    Prius92 Active Member

    Joined:
    Sep 14, 2019
    564
    116
    0
    Location:
    Iowa
    Vehicle:
    2008 Prius
    Model:
    II
    The battery isn't weak tho, it measures fine.

    The temps are not going down and past these temps the charge capacity is reduced. Between 77F and 107F, the max charge is 33.5HP.
    Around 118F, the max charge is 24.1HP.

    If you can't get the battery below 107 degrees, the amount of juice allowed to go into it and out of it, is reduced.

    So you think you have a "weak" battery, but this weakness is imposed by the computer in the hybrid battery in order to keep it from getting even hotter and reducing it's lifespan.

    If you don't have as much power to spare due to this limitation, then the ICE works more, and consumes more gas.
     
    #21 Prius92, Jul 1, 2025
  2. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    7,281
    3,801
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    Maybe the space between the blocks are clogged. Since the fan looks like that, it only makes
    sense that the battery space is full of that also.
    Pull the cover off, and clean! Check all the connectors on the blocks....
     
    #22 ASRDogman, Jul 1, 2025
  3. Prius92

    Prius92 Active Member

    Joined:
    Sep 14, 2019
    564
    116
    0
    Location:
    Iowa
    Vehicle:
    2008 Prius
    Model:
    II
    Do you have a link to your vent tube cooler? Someone mentioned that in another thread.
     
    #23 Prius92, Jul 1, 2025
  4. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    7,281
    3,801
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    If the space between the blocks are blocked so air cannot flow to cool them, it doesn't matter how cold the
    air is going in.

    You should treat the reason for the issue, not the symptom...
     
    #24 ASRDogman, Jul 1, 2025
  5. Brian1954

    Brian1954 Senior Member

    Joined:
    Jan 31, 2021
    1,863
    734
    0
    Location:
    South Central PA, USA
    Vehicle:
    2011 Prius
    Model:
    III
    Can you please answer the question about your hybrid battery asked in post #14?

    Please give a history of any work or module replacements that you have done on the hybrid battery.

    Is this your 2008 Prius? How many miles on the car?

    How have you determined that the battery isn't weak? What measurements have you done?
     
    #25 Brian1954, Jul 1, 2025
    Last edited: Jul 1, 2025
  6. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,472
    4,199
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    There is not vent hose on a Prius. A vent hose are for AC exhaust and laundry drier applications. M
     
    #26 Grit, Jul 2, 2025
  7. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    26,680
    17,470
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    My 2010 doesn't have a vent hose.

    It has two vent hoses.
     
    #27 ChapmanF, Jul 2, 2025
  8. Prius92

    Prius92 Active Member

    Joined:
    Sep 14, 2019
    564
    116
    0
    Location:
    Iowa
    Vehicle:
    2008 Prius
    Model:
    II
    It was reconditioned 2 years ago. Weak cells replaced as well.

    I just did a capacity test this morning and it's 72% of factory capacity, which is good considering these are original Gen2 cells and are approaching 20 years old.

    I've seen 2015's with 100k miles have similar percentages.

    197k miles on the car.
     
    #28 Prius92, Jul 2, 2025
  9. Brian1954

    Brian1954 Senior Member

    Joined:
    Jan 31, 2021
    1,863
    734
    0
    Location:
    South Central PA, USA
    Vehicle:
    2011 Prius
    Model:
    III
    Did you use the Dr Prius app or something else to do this measurement?
     
    #29 Brian1954, Jul 2, 2025
  10. Prius92

    Prius92 Active Member

    Joined:
    Sep 14, 2019
    564
    116
    0
    Location:
    Iowa
    Vehicle:
    2008 Prius
    Model:
    II
    Dr Prius.
     
    #30 Prius92, Jul 2, 2025
    Brian1954 likes this.
(You must log in or sign up to post here.)
Page 2 of 2