Battery cooling fan turning on at low temps

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by _maddie_06, Nov 4, 2022.

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  1. _maddie_06

    _maddie_06 New Member

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    first post. I recently got the p0a80 code and checked in the Dr Prius app. I know I've got at least one block that needs to be replaced. However, earlier I was driving a short distance to get some live data and my hybrid battery cooling fan turned on loudly at around 70 degrees Fahrenheit. I thought it was supposed to turn on around 96f. Does anyone know why it would turn on so much lower?

    Also, I'm trying to decide if I should replace the faulty cells and recondition the battery or get another battery all together. The only thing I can't find is if reconditioning will lower the internal resistance of the cells. I ask because I've got 1 block at 31, 2 at 30, and the rest are either 28-29. I've read that the car will send a signal if the ir hits 30.

    Thanks for any help or info you all may have.
    -Maddy
     
    #1 _maddie_06, Nov 4, 2022
  2. Tombukt2

    Tombukt2 Senior Member

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    The fan is on because the battery is messing up The HV battery.
     
    #2 Tombukt2, Nov 4, 2022
  3. bisco

    bisco cookie crumbler

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    the fan temp sensor is in the battery, not outside the car.

    some say it's too late for recondioning when you get the code
     
    #3 bisco, Nov 4, 2022
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    On a 3rd gen fwiw: monitoring with Scangauge II, I’d see fan speed one or two (has about 5 levels?), on cool evening drive, car fully warmed up, ambient air around 15~18C, battery temp around 35C. Couldn’t hear though.

    still, a noisy, audible fan, could be clogging, and/or running high speed to help failing battery.
     
    #4 Mendel Leisk, Nov 5, 2022
  5. ammdb

    ammdb Active Member

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    If a module is about a volt or more lower than the rest, this indicates a shorted cell in the module, which will cause excessive heat and the fan to turn on. Balancing won't help in this case, but swapping out the bad module might get you down the road for a while longer.
     
    #5 ammdb, Nov 5, 2022
  6. SFO

    SFO Senior Member

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    How many miles on the vehicle, and is this HV battery still the original OEM that it was delivered with?
     
    #6 SFO, Nov 5, 2022
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