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Error Codes: Prius only starts when jumped.

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by ceccorp, Oct 2, 2020.

  1. ceccorp

    ceccorp Junior Member

    Joined:
    Oct 2, 2020
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    Location:
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    Vehicle:
    2009 Prius
    Model:
    II
    I bought a 2009 Prius in this condition. It will only start when jumped, and I often have to disconnect the 12v battery for sometime to get it in ready mode/ in drive.

    I used Techstream to find the following fault codes:

    Hybrid System
    P3000-123 Battery Control System

    P0AA6

    Detail Code 2- 526

    Detail Code 4- 612

    P0A84 Hybrid Battery Pack Cooling Fan 1 Control Circuit Low


    Air Con.
    B1423 Open in Pressure Sensor Circuit / Abnormal Refrigerant Pressure


    ABS/VSC/TRAC
    C1310 HV System Malfunction

    upload_2020-10-2_11-19-52.png

    Any advice on where to start would be greatly appreciated. Would love to have a normally running prius, only other issue is the AC doesn't blow cold. Not sure if that is related or not.


    THANKS!
     
  2. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
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    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Start with the P0AA6-612. That's why the car doesn't want to start (except when it has just had the power disconnected long enough to forget it has a P0AA6-612, and hasn't rediscovered it yet). There is an electrical leakage path within the battery, which you may find responds to a good cleaning, costing you little more than some tedious labor.

    Here's one thread (out of many you could search up) to get an idea what that may entail.

    You may have seen a lot of threads suggesting that high-voltage gloves and safety warnings are overblown, working on the battery is no big deal, all the car's interlocks will protect you, and so on. A lot of that is kind of true when the battery does not have extra electrical leakage paths.

    When it does and you know that's the reason you're working on it, because that's the code you have, the rules change. You do not know what voltages you will encounter where. Use the gloves.

    Once that's sorted, you might look at the cooling fan issue. You can deal with the air conditioning at your leisure, if you care about the air conditioning.

    Don't worry about the C1310; that's the braking computer acknowledging that there are trouble codes in the HV computer, and will go away once you have fixed those.
     
    strawbrad, dolj and SFO like this.
  3. ceccorp

    ceccorp Junior Member

    Joined:
    Oct 2, 2020
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    0
    Location:
    World
    Vehicle:
    2009 Prius
    Model:
    II
    • HV battery assembly
    • Battery ECU
    • System main relay
    • System main resistor
    • Main battery cable
    • No. 2 main battery cable
    • Battery plug
    • No. 2 frame wire
    • Junction block

    Found the battery cooling fan disconnected. Seems the previous owner was pretty clumsy with his work.


    Does anyone have a photos or a diagram of the HV Battery assembly circuit?