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Dr Prius Results - New battery or repair cells?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Kingbhoy, Aug 26, 2020.

  1. Kingbhoy

    Kingbhoy Junior Member

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    Hi guys - I'm after some advice on battery issues,

    after recently facing the "Check Hybrid Battery" Error I decided to do some digging with the Dr Prius App.

    Some history on the car,

    -It's done 165,000 miles

    -Averaged around 45mpg before the error

    Sidenote: when we bought the car the interior was filthy.... I don't know if the previous owner had dogs, pigs, or regularly drove through swamps but there was mud and dirt in places I didn't know existed. I wonder if this has clogged up the battery fan and is playing a role?

    I've been offered either a repair job of faulty cells, or a full replacement. Any advice or suggestions based on these results would be much appreciated.

    Here are the results of testing:

    Before any tests

    Test Results

    Stats Post test

    Thanks in advance.
     
  2. sam spade 2

    sam spade 2 Senior Member

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    You should definitely check the battery cooling fan.

    "Fixing" by replacing only the really bad cells is a band aid solution.......which is likely to last from a few days to a few months before other cells fail again.

    Assuming that there probably is a LARGE price difference between those two options, only you can decide if price is more important than repeated inconvenience.
    How long you intend to keep the vehicle should figure into your decision too.
     
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  3. davecook89t

    davecook89t Senior Member

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    Other than the screen showing the Life Expectancy Test, your results don't look bad. The voltage differences you are showing are below the threshold that would normally create an error code and the battery temperatures shown do not indicate that the battery is overheating. Given the history of the car, it is probably worth taking a look at the battery fan, regardless, and what needs to be recognized about the screen shots you have provided is that they are just snapshots of your battery parameters at 2 different points in time, which may not reveal that much. Further, they were both taken when the battery is at a low State of Charge. Taking a screen shot after force charging the battery to get to a higher SOC might show a different picture, but really the most revealing type of analysis you could do would be to log the parameter values under both high and low SOC conditions as you drive down the road. There are functions in either Torque Pro or Hybrid Assistant for that purpose. I'm not aware of whether that can be done using Dr. Prius by itself.
     
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  4. bisco

    bisco cookie crumbler

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    clean the inside of the battery case too.

    if you wind up needing a new one, consider how much longer you want to keep the car, and the egr circuit issue.
     
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  5. Grit

    Grit Senior Member

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    Doesn't look like a HV fan issue, you can clearly see >8 volts on it.
    Doesn't look like a HV fan filter issue either, the 3 temp sensor shows < 70F. If filter needed cleaning, your temps would be in the 100Fs.
    Just from 2 screenshots, voltage difference between highest & lowest voltage are within normal ranges- no more than 0.3 volts difference.

    But first I would pull the CEL and then check 12v bat. Some fella had the dreaded p080a code and changed the 12v battery, the code went away.

    My next edumacated guess after the 12v check would be buss bars.
     
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  6. Kingbhoy

    Kingbhoy Junior Member

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    Thanks for all the replies guys.

    The CEL displayed is also the p080a code.

    I checked the 12v stats through the vehicle maintenance dashboard which brought up a 11.3V reading.

    Looks to me like it would be worth first replacing the 12V battery and see what that does, rather than the £1500 new HV cost.
     
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  7. sam spade 2

    sam spade 2 Senior Member

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    I agree. Mostly because 11.3 volts with little or no load indicates a DEAD batttery.
    Make sure that your new one is fully charged and check the charging voltage after install.
    It should be around 13.6 volts.