Further hybrid system testing and help needed.

Discussion in 'Gen 3 Prius Main Forum' started by Prius92, Jun 28, 2025 at 1:31 PM.

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  1. Prius92

    Prius92 Active Member

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    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 at 8:31 PM
  2. ASRDogman

    ASRDogman Senior Member

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    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 at 10:17 PM
  3. Prius92

    Prius92 Active Member

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    Do you have a link to your vent tube cooler? Someone mentioned that in another thread.
     
    #23 Prius92, Jul 1, 2025 at 10:20 PM
  4. ASRDogman

    ASRDogman Senior Member

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    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 at 10:24 PM
  5. Brian1954

    Brian1954 Senior Member

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    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 at 11:05 PM
    Last edited: Jul 1, 2025 at 11:25 PM
  6. Grit

    Grit Senior Member

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    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 at 12:08 AM
  7. ChapmanF

    ChapmanF Senior Member

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    My 2010 doesn't have a vent hose.

    It has two vent hoses.
     
    #27 ChapmanF, Jul 2, 2025 at 8:37 AM
  8. Prius92

    Prius92 Active Member

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    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 at 8:39 AM
  9. Brian1954

    Brian1954 Senior Member

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    Did you use the Dr Prius app or something else to do this measurement?
     
    #29 Brian1954, Jul 2, 2025 at 9:06 AM
  10. Prius92

    Prius92 Active Member

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    Dr Prius.
     
    #30 Prius92, Jul 2, 2025 at 9:09 AM
    Brian1954 likes this.
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