All 14 battery pairs show great voltage, But CEL replace hybrid Batt

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by poway, Aug 7, 2026 at 12:42 PM.

  1. poway

    poway Junior Member

    Joined:
    Sep 1, 2011
    20
    1
    0
    Location:
    Pensacola FL
    Vehicle:
    2010 Prius
    Model:
    II
    Hello all,
    2013 Prius V, 230,000 miles. Replaced 3 battery packs 6 months ago. All 14 pairs show great voltage. Car worked great for 6 months. Left car unused in FL 90 degree weather. Now getting CEL P0A80 (check engine light) to replace hybrid battery. Along with C1259HV control system regenerative malfunction. Replaced the two expensive brake components in engine compartment in Jan. I believe this code is related to the Hybrid batt. After I clear the CEL it takes approximately 50 miles for it to reappear. It's after the second start, of the day. Any ideas on how to proceed greatly appreciated! IMG_1046.jpeg IMG_1048.jpeg
     
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    115,439
    52,848
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    are you testing the battery under load?

    when you say battery packs, do you mean modules?
     
  3. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    28,720
    19,019
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
  4. Brian1954

    Brian1954 Senior Member

    Joined:
    Jan 31, 2021
    2,679
    1,071
    0
    Location:
    South Central PA, USA
    Vehicle:
    2011 Prius
    Model:
    III
    To help troubleshoot, you need a good scanner that can read the freeze frame data for the P0A80 code. The freeze frame data will show the voltages of the 14 battery blocks when the P0A80 was triggered. Looking at the battery block voltages should tell you which battery block is the problem.