1. Attachments are working again! Check out this thread for more details and to report any other bugs.

HV Battery: Can I clean corrosion myself?

Discussion in 'Gen 2 Prius Technical Discussion' started by Buffalo Bill’s Prius, Feb 9, 2023.

  1. Buffalo Bill’s Prius

    Joined:
    Feb 8, 2023
    9
    0
    0
    Location:
    Orange County
    Vehicle:
    2005 Prius
    Model:
    Base
    Greetings folks

    After displaying the infamous red triangle my 05 Prius would not shift out of Neutral.

    After clearing the triangle by unplugging the 12v I reluctantly drove to the dealership. (I spent 3k at this dealer for a stolen cat)

    After a 300$ diagnostic on the battery they determined the following:
    -The HV battery cells hold a charge and are functioning correctly
    -Some metal components are “corroded by moisture” and interfere with the charge
    -Yota dealer does not clean HV packs and recommends a new 4K battery.

    My service provider was a kind and frank person. Towards the end of the conversation he mentioned that
    -it would be a waste of money
    -if it were his car he would clean it himself
    -I could use YouTube to learn (or forums like this
    -I could get a shop to do it “for time”

    My question is:
    Can I do this myself? If so how? And, how dangerous is this for a guy that has no experience with cars?
     

    Attached Files:

  2. mr_guy_mann

    mr_guy_mann Senior Member

    Joined:
    Sep 3, 2020
    3,253
    1,359
    0
    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
    The visible corrosion is typical and "mostly irrelevant". I assume that you have a P0AA6 code (loss of HV isolation). That means that there is some "electrical connection" between part of the high voltage system and the metal of the car body.

    It could be a crack in a battery module (that lets some electrolyte seep out), or a fault in any other part of the HV system - such as the inverter or transmission. (Cleaning surface corrosion on the battery won't fix the cause if it is a leaking module).

    The code also has an INF or sub code that gives more details about what the ecu thinks is wrong. The ecu first sets a "general problem" INF code when the master warning light comes on. Turning the car off and trying to power up again will usually set a second INF code that gives a better idea of where the problem is - then you would have scan the car again with a Prius capable scantool.

    Posted via the PriusChat mobile app.
     
  3. Buffalo Bill’s Prius

    Joined:
    Feb 8, 2023
    9
    0
    0
    Location:
    Orange County
    Vehicle:
    2005 Prius
    Model:
    Base
    Thanks so much for taking the time to respond
    I was just watching some videos in preparation to remove the battery and clean the bus bars (which now seems like a wasted endeavor)
    I asked the service provider for the codes and indeed it was a P0AA6 code but he didn’t provide the sub codes.
    I am going to attempt the clean the corrosion I hopes of solving the issue.
    Meanwhile I will order a ODB reader to get the subcodes.

    Silly question: if it is an inverter or transmission problem then would replacing the battery entirely solve the issue? I assume it depends on the codes

    thankyob
     
  4. Buffalo Bill’s Prius

    Joined:
    Feb 8, 2023
    9
    0
    0
    Location:
    Orange County
    Vehicle:
    2005 Prius
    Model:
    Base
    I have an update

    I ran the simple test to find the leak as described in a recommended YouTube video. I cleared the codes and did the test.
    1. Start car on not ready mode (cause is battery)
    2. Car in ready mode (cause is inverter)
    3. Drive (cause is transmission)

    I got the triangle in the beginning so it must be a HV leak. I am still preparing to dismantle the battery (very scared)