How degraded can a hybrid pack get before throwing the P0A80 and red triangle?

Discussion in 'Gen 3 Prius Technical Discussion' started by koukilights, Mar 11, 2025 at 6:35 PM.

  1. koukilights

    koukilights Junior Member

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    I have a 2011, 315k miles on it. And I got the P0A80 code the other day.

    I got the Dr Prius app, looked at which blocks were weak, and it said block 7 and maybe block 8.

    So I got 3 modules off ebay and tore my pack apart.

    I'm reconditioning my modules with a hobby battery NiMH cycler, and I'm surprised at how low some of the capacity on these modules are. They should be around 5000mAh at this age, but 1 was down to 800 after 3 cycles on the charger. 1 was down to 1200mAh. Most in the middle of the pack were around 2500mAh. Most on the outside edges were around 4000mAh.

    So, I guess as long as the battery doesn't seriously get depleted with hard acceleration when low, the pack will hide any issues and you won't get a CEL?
     
    #1 koukilights, Mar 11, 2025 at 6:35 PM
  2. vvillovv

    vvillovv Senior Member

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    I'm surprised that you're surprised by the state of the 13 year old modules that came out of a 2011 Prius with 315 K miles on its ODO.
     
    #2 vvillovv, Mar 11, 2025 at 10:48 PM
  3. koukilights

    koukilights Junior Member

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    I'm not saying that I expected 26 modules to be ripping along at 5500mAh right away. I saw on the Dr Prius app, 1 block that was consistently lower than the others, and with the P0A80 CEL only tripping once I thought that meant that the pack was good with the exception of 1 block (2 modules).

    But I was surprised to see that close to half the modules were underperforming in the 2000mAh range and I only got the CEL one time.
     
    #3 koukilights, Mar 11, 2025 at 10:56 PM
  4. vvillovv

    vvillovv Senior Member

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    Yeah, I read that in your OP ! Is there a reason you repeated how surprised you were from the cycling results
     
    #4 vvillovv, Mar 11, 2025 at 11:39 PM
  5. MAX2

    MAX2 Active Member

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    When the high-voltage battery modules age equally and lose their capacity, it is not noticeable to the eye. A slight shortness of breath appears, like when climbing a high ladder, but the battery still works, even if all modules are equal to 2A x h. It only affects the deteriorated mileage per gallon.

    But if one module drops lower than the others, it does not matter how many 5A x h or 4A x h remain in the others. The error is guaranteed to appear.
     
    #5 MAX2, Mar 12, 2025 at 5:18 AM
  6. Brian1954

    Brian1954 Senior Member

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    How did you determine that a 14 year old hybrid battery should have modules at 5000mAh capacity?
     
    #6 Brian1954, Mar 12, 2025 at 9:31 AM
    DirkAshburn likes this.
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