Further hybrid system testing and help needed.

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

  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.
     
  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....
     
  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.
     
  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...
     
  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