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

2005 DTC P0A80 Diagnosis

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Eeyore, Jan 12, 2018.

  1. Eeyore

    Eeyore Junior Member

    Joined:
    Jan 12, 2018
    18
    1
    0
    Location:
    Salem Oregon
    Vehicle:
    2005 Prius
    Model:
    Four
    For clarification, is the ECU being talked about the "Battery Smart Unit?"
     
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,693
    48,945
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    any corrosion inside the battery case, buss bars and etc?
     
  3. Eeyore

    Eeyore Junior Member

    Joined:
    Jan 12, 2018
    18
    1
    0
    Location:
    Salem Oregon
    Vehicle:
    2005 Prius
    Model:
    Four
    I haven't torn the housing down just yet. I'm thinking about taking it to Toyota to read the 3 digit sub code before I dig into my own troubleshooting.
     
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,693
    48,945
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    sounds like a good idea.
     
    Raytheeagle likes this.
  5. Eeyore

    Eeyore Junior Member

    Joined:
    Jan 12, 2018
    18
    1
    0
    Location:
    Salem Oregon
    Vehicle:
    2005 Prius
    Model:
    Four
    Does anyone know if I would have to pre-charge (or balance) the battery pack of my second Prius before installation? (If it turns out to be the HV battery)
     
  6. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,693
    48,945
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    depends on the pack. is it new from toyota? if not, you should probably recondition it.
     
  7. Eeyore

    Eeyore Junior Member

    Joined:
    Jan 12, 2018
    18
    1
    0
    Location:
    Salem Oregon
    Vehicle:
    2005 Prius
    Model:
    Four
    It's a refurbished pack from my sister-in-law's 2005 with a blown engine. It's been sitting for a year.
     
  8. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,476
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    Charge and balance it, that will give it the best chance;).

    But this is not guarantee :(.

    Good luck and keep us posted (y).
     
    JC91006 and bisco like this.
  9. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,693
    48,945
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    over 6 months can be bad. you can try it, but it would be prudent to recondition first. if you install it and it works, it won't get better from driving like the reconditioner.
     
    Raytheeagle likes this.
  10. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,470
    8,383
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    You would need to put that battery on a charger before installing it. A 13 year old battery would not work properly after sitting a year, it'll be out of balance
     
    m.wynn and Raytheeagle like this.
  11. Eeyore

    Eeyore Junior Member

    Joined:
    Jan 12, 2018
    18
    1
    0
    Location:
    Salem Oregon
    Vehicle:
    2005 Prius
    Model:
    Four
    Thanks for the info! I'll take it to Toyota for confirmation. I'm going to then take it to my department and have both battery packs balanced.

    Where is the HV ECU located? Is it the Smart Unit or the one located in the dash?
     
    Raytheeagle likes this.
  12. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,470
    8,383
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    You don't have to mess with the battery ecu, they rarely go bad. But it's located on the battery pack. It's the rectangular box
     
    m.wynn, valde3 and Raytheeagle like this.
  13. Eeyore

    Eeyore Junior Member

    Joined:
    Jan 12, 2018
    18
    1
    0
    Location:
    Salem Oregon
    Vehicle:
    2005 Prius
    Model:
    Four
    I took it to the local Toyota service center and they said it's the battery. I concur with their diagnosis, seeing as the car went into limp mode at the light just before their driveway.

    I was watching the Torque app the entire 10 mile drive. Everything started out perfectly fine. I did notice that the resistance of blocks 1 and 14 were slightly lower than the rest. Under load, the end blocks were 500mV to 800mV lower than the center blocks. When the car went into limp mode, the battery fan kicked on for the first time in the 2 years we've owned it, and block 8 dropped an entire volt lower than the others. After seeing this, I think it's been block 8 the entire time causing errors. While at a stop, block 8 would steadily drop by 100mV every few seconds. I had to keep it above 17V, otherwise it would drastically drop lower than the others...

    Now here's the thing, I don't have a ton of money for the repairs, and this car literally costs half as much to run than my other. What should I do? I have a spare 2005 Prius with a blown engine (possibly inverter as well) and a refurbished battery pack that was working perfectly. The spare has been sitting for a year. Do I replace the individual batteries on MY pack, or charge the refurb pack, and how would I do that my self? I don't have access to my schools reconditioning equipment anymore.
     
    #33 Eeyore, Jan 22, 2018
    Last edited: Jan 22, 2018
  14. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,693
    48,945
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    you can buy a hobby charger and do one module at a time.
     
  15. Eeyore

    Eeyore Junior Member

    Joined:
    Jan 12, 2018
    18
    1
    0
    Location:
    Salem Oregon
    Vehicle:
    2005 Prius
    Model:
    Four
    Can anyone recommend a cheap charger and a method of discharge?
     
  16. Eeyore

    Eeyore Junior Member

    Joined:
    Jan 12, 2018
    18
    1
    0
    Location:
    Salem Oregon
    Vehicle:
    2005 Prius
    Model:
    Four
    I was looking at the IMAX B6AC V2 charger for conditioning my pack. How many would I need to get to do this in about a week or two?
     
  17. Eeyore

    Eeyore Junior Member

    Joined:
    Jan 12, 2018
    18
    1
    0
    Location:
    Salem Oregon
    Vehicle:
    2005 Prius
    Model:
    Four
    Anyone?

    Would 4 be enough to charge my extra pack that's been sitting flat for a year?
     
  18. Michael Cyr

    Michael Cyr Junior Member

    Joined:
    Jul 23, 2014
    9
    3
    0
    Location:
    Belgrade, ME
    Vehicle:
    2008 Prius
    Model:
    Four
    Just for anyone else thinking about the IMAX B6AC V2. Don't. I have one for my drone and it can only discharge at about .7amp. It also doesn't seem to have a max NIMH voltage cutoff so I use the mAmp/hr cutoff.