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High frequency noise and abormal voltage in hybrid battery

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by prriuss, Sep 9, 2020.

  1. prriuss

    prriuss New Member

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    Location:
    Dallas
    Vehicle:
    2012 Prius
    Model:
    Three
    My 2012 Prius has 130,000 miles. When I am driving today, I hear high frequency noise when I am accelerating and using the brake. There is no noise when the car stops. I do not notice any mileage difference which is still around 58 mpg with ac on. Then I use the Dr. Prius app to check the battery. It shows the voltage is extremely high when I am braking. The voltage sometimes drops to extremely low when I am accelerating gently. I also check the OBD code and there is no code. Is something going to fail soon?
     

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    #1 prriuss, Sep 9, 2020
  2. Grit

    Grit Senior Member

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    Wilkes Land
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    o_Oo_Oo_Oo_Oo_Oo_Oo_O
     
    #2 Grit, Sep 9, 2020
  3. ChapmanF

    ChapmanF Senior Member

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    IV
    Those internal resistance figures add up to about 0.349 Ω. That by itself will account for about 18 volts of sag when you're pulling 51 amps out, or 25 volts of excess when you're pushing 73 amps in. What's left doesn't seem like outlandish voltages to me for NiMH modules, though maybe someone else will have more data to compare to.
     
    #3 ChapmanF, Sep 9, 2020
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