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

HV Battery Testing

Discussion in 'Gen 3 Prius Technical Discussion' started by Dan Flynn, Aug 28, 2017.

  1. Dan Flynn

    Dan Flynn New Member

    Joined:
    Aug 28, 2017
    1
    0
    0
    Location:
    Minden, NV
    Vehicle:
    2010 Prius
    Model:
    III
    Greetings, all. First time posting, though I've been searching the forum for input on my particular problem. No luck finding someone who's posted this one before, so Here I am. My 2010 Prius, with 381,000 miles (no, that's not a typo) got the dreaded P0A80 error code this week. Rather than spend the $3500 that the dealership quoted me, I went online and watched videos, and read here about testing individual cells within the HV Battery, to identify bad cells. After exposing all the cells, with the Bus bars removed, I find that in the un-loaded state, they all have Voltages from 7.71 to 7.74V. There are zero cells that are outside of those parameters, and I went through them multiple times. What's my next step, in terms of testing? I'm assuming that if I put a load against each cell, I might see a more dramatic difference among the cells. Am I on the right path? I'm open to any input.
     
    #1 Dan Flynn, Aug 28, 2017
  2. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,525
    8,428
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    If the battery is out of the car, let it sit for a week (7 days) and the bad modules will self discharge and you'll see the bad ones. Alternatively, you can try load testing all the modules too and clean the bus bars while you're at it

    This battery pack is not going to last you a long time, even after you replace your bad modules. The pack is worn and should be replaced. You can probably find a junk yard pack for $1000 or find someone parting out a good pack from a wreck
     
    #2 JC91006, Aug 28, 2017
    V Sport Wagon likes this.
  3. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
    5,302
    4,241
    0
    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Welcome to PriusChat!!

    Clean up the HV battery fan, find and replace the bad cell(s), pick up a http://hybridautomotive.com grid charger and give it a proper balance/reconditioning.
     
    #3 SFO, Aug 28, 2017
    WilDavis and Raytheeagle like this.
  4. Fred_H

    Fred_H Misoversimplifier

    Joined:
    Apr 20, 2007
    555
    476
    28
    Location:
    Germany
    Vehicle:
    2007 Prius
    Model:
    Touring
    You might also want to check both ends of all 15 voltage sensing wires. If there is a broken or poor connection, then the battery ECU will think that one or two of the 14 measured battery blocks has out of spec voltage.
     
    #4 Fred_H, Aug 30, 2017
    SFO likes this.
  5. robinredd1

    robinredd1 Junior Member

    Joined:
    Jun 11, 2020
    37
    1
    0
    Location:
    Rio Linda, California
    Vehicle:
    2007 Prius
    Model:
    Three Touring
    fastest easy way to find bad models in 3 minutes
     
    #5 robinredd1, Aug 18, 2024
(You must log in or sign up to post here.)