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2007 prius - p0a80 after bad cell replaced

Discussion in 'Gen 2 Prius Technical Discussion' started by Paul Soldridge, May 3, 2017.

  1. Paul Soldridge

    Paul Soldridge Junior Member

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    Ok bought an 2007 with 88,000 miles - nice condition. Had the hybrid battery code on when I bought it, but I have replaced cells before. I tested all the cells and they were all in the 8.24-8.14V range -except one was 6.94. I charged up a replacement cell to be in the 8.2 range and installed. I drove the car for about 350 miles over a month with no issues - was feeling real good about the fix. I then noticed some issues - the battery level would drop right after you started the car from an overnight rest, and it would charge and discharge to purple pretty quick. Then the lights all came back on today with the p0a80 code.

    Could this be anything other than the cell I replaced not being within range of the others? I have not torn the battery out.
     
  2. ericbecky

    ericbecky Hybrid Battery Hero

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    Use your scanner and look at all the cells voltages.

    If you do not have a scanner, the software and hardware costs less than $50.
    Bluetooth OBDII + Torque app + Android phone/tablet.

    You NEED to be able to see this data if you want to avoid ripping apart your entire car and battery just to take a few voltage measurements.

    It may be that the module replaced is fine, but now it is a different module. Classic, Whack-A-Mole sequence of events.

    Or it could be the wiring/connectors.
    Did you inspect the wiring?
    Did you use your torque wrench (less than $15) to properly torque each terminal connection as well as the HV connections at the contactors?

    A Bluetooth OBDII scanner could point you in the right direction within 30 seconds.

    But if you don't have one, then take some time and backtrack through the repair you just did. Check/recheck connections. Check the orand plug. Check the wires. Check the computer harness for corrosion. Etc

    Call me if you want to bounce ideas off of someone. Happy to help.
     
    M in KC, Raytheeagle and SFO like this.
  3. fotomoto

    fotomoto Senior Member

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    ^ Everything Eric said.

    Balancing the pack is recommended after replacing a module (FYI, you replaced a module not a cell). Here's what I did:

    My P0A080 fault code and battery rebuild | PriusChat
     
  4. ericbecky

    ericbecky Hybrid Battery Hero

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    We talked on the phone.
    Will get things setup so he can see stuff in Torque.

    Anyone know if the HV Battery parameters are missing as a pre-loaded option in the drop down menu from the FREE version.
    Others have reported they are available in the PAID version.

    I have had the PAID version for a long time and I loaded them myself back when they were not a pre-loaded option in the list that came with the app.
     
    #4 ericbecky, May 3, 2017
    Last edited: May 3, 2017
  5. Paul Soldridge

    Paul Soldridge Junior Member

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    Received a second code - P3021. This points to block 11. I removed the battery pack (1/2 hour) and then tested all the cells. One of the modules was much lower than all the others, and it was located in the 11 block. It also drained voltage a good amount over a few hours. This is obviously the problem. When I checked my readings from the last time I tested the battery - only 350 miles ago, the current bad cell was the lowest of all the cells - it was still at 8.15V though, and the one I had to replace at that time was 6.94V.
    The two failed modules were not next to each other, but my inclination is to now get a remand battery pack. This car has low miles, but it spent much of its life in the Southwest and I think the heat and the lack of use has been tough on the battery.
    Ericbecky is a tremendous help, and I appreciate the amount of time he spent on the phone educating me further on the battery!
     
  6. JC91006

    JC91006 Senior Member

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    Since the battery is out, replace the module in block 11

    SM-N900P ?
     
  7. M in KC

    M in KC Active Member

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    Do what yo will, but at such low mileage and if the car is in generally good repair I would look at a new HV battery from Toyota. 3yr warranty if they install, 1 year if you install. But you would know for cock certain your HV battery would be all but bullet-proof for another 10 years.
     
  8. Paul Soldridge

    Paul Soldridge Junior Member

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    The cheap guy in me wants to replace the bad cell and put it back together - I have a spare cell. I am probably going to do a load test on the remaining cells to see how they perform. I am leaning toward a Dorman replacement.
     
  9. JC91006

    JC91006 Senior Member

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    If you have the spare, put it in. If it doesn't work, go with dorman.

    Sometimes there will be more than 1 failed module in a pack

    SM-N900P ?
     
  10. BillG

    BillG Junior Member

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    I just rebuilt a 2010that had the dread p0a80 code. It ran fine the first day. Now I have the same code. Using techstream. All of the voltages are spot on 16.2to 16.23 for each pair. While driving and sitting the voltages stay extremely close. One never drops alot more than any others? What could this be? On techstream when I open the hybrid battery and pull the codes it shows block 8 is at 12.9 volts. but when I am doing active test it never drops more than any others. How do I tell if this code was from the first time or from my rebuild. I bought and used the prolong charger dis charger. Bought the upgrade kit not the one with the light bulb. I rebuilt this for a freind so now I am curious what could be wrong. I cleaned all the bus bars, they look brand new. cleaned the fan. any ideas?
     
  11. 2k1Toaster

    2k1Toaster Brand New Prius Batteries

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    After replacing the battery you should clear all the codes. Is your "active test" the equivalent of flooring it in reverse? If not, then that's not similar enough to driving to be a real test. Find a nice steep hill, and reverse up it.
     
  12. ericbecky

    ericbecky Hybrid Battery Hero

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    Also record the voktage while driving.
    Open the pack up and carefully inspect the ring terminal crimp for any breaks.

    Did you make sure 100% that you correctly tightened each of the nuts on the HV battery with an inch-pound torque wrench?
     
  13. Kenrico

    Kenrico Member

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    You have replaced a cell in yours ..maybe 2 now .. don't go Dormans ..basically you are paying for something you already have ..a used pack that has had failed modules replaced.

    Technically you and BIIG are both on the same path..the aged HV battery will continue to trigger the red Triangle light . You will continue to play whack a mole until a newer , low mileage pack is obtained .

    If I had to do over again would bite the bullet and done dealer pack or 2k1Toasters cylindrical cells ..I played whack a mole for close to two years ..replacing close to half the pack - 1 or 2 modules at at time ..sometimes dropping within a month of being back on the road ..sometimes as long as 6 monthes .. but those aged modules will lose a cell and throw the red Triangle code .

    Kenny
     
  14. ericbecky

    ericbecky Hybrid Battery Hero

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    Thanks for the honest assessment kenrico.
    Especially the feedback about how sometimes the replacement lasted less than a month, sometimes 6 months. That is good information for people to think about.
     
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  15. Kenrico

    Kenrico Member

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    Yes , the OP comment about keeping it on the cheap made me think of my experience . It was cheap , assume $500 in cells total . But I couldn't hop in the car and go to Vegas ..had to keep local, as there is no rhyme or reason to when the code would trip - was not an issue as long as I was local and could limp home .

    Maybe we should call it kick the can instead of whack a mole .. but the truth is neither module replacement or Dormans is a 2 year solution for an aged pack in my opinion.

    Kenny
     
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  16. BillG

    BillG Junior Member

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    I forgot to reset the codes but also found that that dreaded code isnt actually usually a battery failure but a grounding wire issue with the HBCAN.
     
  17. BillG

    BillG Junior Member

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    I have actually had good luck rebuilding. I am still very very green but I have put over 50k on my first rebuild. and have rebuilt several others and thus far no issues. Besides my own like not clearing codes. Overall I test voltages at rest, voltages under load, Use tech stream, do the 3 cycle charge discharge with prolong deluxe reconditioning package. I also replace Wire frame #2 and bus bars. ( $45 bucks so I think it is worth the extra cost as I have seen super tiny crack cause the dreaded P3030 code) I have not had any fail yet. I want to take it to the next level and start matching by more accurate capacity ( mah) I am far from a pro and most guys on here have forgotten more than I know but I keep reading and learning. Now I am trying to find the right charge dis charge boards that will work. ( think I have found some on Ebay ) to build something similar to 30 rc chargers in one system but without the pc data logging. The Hybrid market is only going to grow and the need for this type of repair will be there. The Dealers do not rebuild but replace. My thought is replacing may be a good option but it is expensive. Also if I have 200k on my car why would one want to put $3500-$4500 new battery in when you could put a grand or so in a good rebuild and get 75k or maybe more miles out. By then there is going to be alot of other stuff broke on the car. Most people don;t keep their cars for 300 -400k. Sorry long winded but just my thoughts. Thanks as always
     
    #17 BillG, Mar 20, 2018
    Last edited: Mar 20, 2018
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  18. macondo100

    macondo100 Junior Member

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    thanks; got a 2006 with 170k and just got this p0a80 and agree on not spending 4-5k on a new hybrid battery.
     
  19. ericbecky

    ericbecky Hybrid Battery Hero

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    No need to spend $4,000+

    For under $2,000 you can get a brand new battery from Toyota this afternoon and have it in tonight. Done. Never think about it again.

    But certainly not you enjoy the challenge of messing with the packs. Go for it as long as it is still fun for you. It certainly will save some money, but you have to spend much more time.

    Even the big companies that have $100,000 equipment have a hard time making used packs last very long.
    I've had 3 Used packs from large company fail in the last week. Most are about 3 years old. There isn't some special sauce that will make used batteries last forever. They will die when they die .
    One thing I can guarantee is that they will always die way before a New pack.