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P0A80 and P3017...Bad cell or corrosion?

Discussion in 'Gen 2 Prius Main Forum' started by universeisgr8, Jun 21, 2020.

  1. universeisgr8

    universeisgr8 New Member

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    Hello all and first thanks for helping each other out.
    Problem and symptoms:
    Recently, got red triangle and other orange lights on my 2007 prius with 170K miles. The battery indicator on the LCD is charging and discharging significantly more rapidly than before. The hybrid cooling fan is blowing fast all the time and i can hear air noise from the rear vent next to the rear seat.

    What i tried:
    I have a bluetooth OBD scanner, so i checked with torque pro. There were two codes: P0A80 and P3017 telling me that block 7 has issues. Block 1, 2, 3 temperatures were 85, 90, 84 degrees. I also measured voltages of each block with and without load. Most block voltages were pretty stable at around 17v but for block 7, the voltage would sometimes go higher than 17 and sometimes drop below 17. I also checked with Dr. prius and it shows issues with block 7 current. Based on this behavior, my guess is that there may be corrosion on block 7 bus bars which has increased the resistance.

    I have never done this work as a DIY but i can do it. However, from those who have more experience, i am wondering whether this could just be a corrosion problem or a cell might be weak. this will help me plan the DIY and buy cells if needed. Prior to the issue, i was consistently getting mileage of 44-45/gallon.
     
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  2. AzusaPrius

    AzusaPrius Senior Member

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    You say you can do it then remove the orange safety plug and all bus bar assembly, then test the voltage each cell module on their own. There you will see the bad module in block 7.

    Clean the bus bars up with a vinegar solution.

    Replace any module that reads anywhere in the 6 volt range.

    Posted via the PriusChat mobile app.
     
  3. SFO

    SFO Senior Member

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    Welcome to PriusChat!!

    Don't forget to clean the HV battery fan while everything is taken apart.
     
  4. universeisgr8

    universeisgr8 New Member

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    Thanks for the advice. I was hoping if someone had been in a similar situation because i can order the cell before taking the battery apart and have it ready when i need it, but if i dont need it then i don't want to order the cells proactively. Anyway, i guess i will have to test it first to be sure.
     
  5. universeisgr8

    universeisgr8 New Member

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    Absolutely. That's my plan as well. thanks.
     
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  6. strawbrad

    strawbrad http://minnesotahybridbatteries.com

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    Been there and done that hundreds of times. It's not corrosion. You have at least one failed battery module.
     
  7. AzusaPrius

    AzusaPrius Senior Member

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    Exactly

    Posted via the PriusChat mobile app.
     
  8. universeisgr8

    universeisgr8 New Member

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    One more thing puzzles me. I have seen many sellers listing different voltages for used battery modules anywhere from 7.4+ to 7.8+. What should be the minimum voltage of a cell for buying consideration? And out of curiosity, what is the voltage of a brand new cell module?
     
  9. AzusaPrius

    AzusaPrius Senior Member

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    Those are good voltages and you dont want one near 6 volts.

    Posted via the PriusChat mobile app.
     
  10. dolj

    dolj Senior Member

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    Voltage is not nearly as important as capacity. Capacity should match your other modules as best as possible. Use an RC hobby charger to calculate capacity.

    You can also work out a relative capacity (relative to your other modules) by applying a known load resistance timed to a set voltage, say to 7.2 V. Start with a fully charged module. A good module should be able to achieve somewhere in the 8.4 V territory when fully charged. You can use those known values to calculate capacity, but just using the time taken is good enough to use as a relative comparison.
     
  11. universeisgr8

    universeisgr8 New Member

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    Thanks everyone for the help. Went through the effort, initially it was a bit intimidating, removed battery, brought it inside, had one bad cell. Replaced it, installation was easier and now car is fixed.
     
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  12. AzusaPrius

    AzusaPrius Senior Member

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    As Smithers from the Simpsons would say....Excellent.

    Posted via the PriusChat mobile app.
     
  13. 2005with259k

    2005with259k Junior Member

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    Thanks for asking this question! I just crashed my ‘05 into a pole due to icey roads up here in Saginaw Michigan. My ‘05 has 276k. I found an 2005 with 147k with those exact codes.

    Question with those codes would that be why the car I test drove took soooo looong to accelerate? Is that the “limp mode” everybody talks about? I mean it got up to the required 45mph on the street in the city I was in, but it revved real high and took forever. The Hybrid battery fan in backseat was sure sign it was going full force never shut off for whole 15-20 min test drive. Weird thing is the car went from sitting with one bar to staying charged at 100% the whole 20 minute drive too? I got a P3000 too. Any help? Should I drive it 100 miles home and put my battery in from my ‘05?
     
  14. universeisgr8

    universeisgr8 New Member

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    Yes one or more bad hybrid cells would be the reason. After i posted my question, i fixed it myself by replacing the two bad cells. The acceleration issue was identical in my car also because battery is not providing any power and the small prius engine is working very hard to get the car going. Changing cell is not that difficult if you are handy with tools.
     
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  15. 2005with259k

    2005with259k Junior Member

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    I am REALLY accident prone and clumsy. I fix things that I know I can do without hurting myself, or being overwhelming. My mechanic will swap my batteries for only $130. He is a really nice guy. I am positive you would never see a post from me again if I tried doing it myself.
     
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