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2009 battery deteriorating

Discussion in 'Gen 2 Prius Main Forum' started by Drazic, Aug 20, 2021.

  1. Drazic

    Drazic Junior Member

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    Aug 16, 2021
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    Location:
    Palmerston NT
    Vehicle:
    2009 Prius
    Model:
    i-Tech
    Hello people of Prius chat
    So at the start of the week I got a message come up on my 2009 Prius saying "Check hybrid system"
    and just yesterday I got someone from Insurance come to diagnose my car, and he said that it was a deteriorating battery. This pretty much means I need to get it to a Toyota shop to get a new battery put in, I am the 2nd owner of this car since about March this year, and I was slightly aware of this risk. I want to know if it is okay to drive this car to the mechanics which is 25 kilometres away, or will it do further damage to my car?
     
    #1 Drazic, Aug 20, 2021
  2. ChapmanF

    ChapmanF Senior Member

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    Location:
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    Vehicle:
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    IV
    Probably won't further damage the car. But it is much better to post the actual trouble codes here (look like P or C or B or U with four digits or letters after) than some paraphrase like "deteriorating battery". If the person who came to diagnose the car didn't give the actual codes, I would ask for them.

    If you post the codes here, we can tell you more.
     
    #2 ChapmanF, Aug 20, 2021
  3. TMR-JWAP

    TMR-JWAP Senior Member

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    Vehicle:
    2007 Prius
    Model:
    Touring
    If it is 'deterioration' it should be a P0A7F code and will maintain normal drivability until additional failure occurs. This code is effectively saying a battery is wearing evenly, but showing it's age. Not necessarily a OMG moment.

    P0A7F.jpg


    MONITOR DESCRIPTION The battery ECU calculates the resistance of the HV battery through amperage and voltage, and uses this resistance to determine the extent of deterioration of the HV battery. If the battery ECU detects that the resistance of the HV battery has exceeded the standard, it determines that malfunction has occurred. In addition, the battery ECU monitors the SOC, and if the difference between the maximum and minimum SOC values exceeds the standard, it determines that malfunction has occurred. When either of the malfunction detection conditions is met, the battery ECU illuminates the MIL and sets a DTC.
     
    #3 TMR-JWAP, Aug 20, 2021
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