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Would you buy this 2015 Prius? HV Battery Balance Problems

Discussion in 'Gen 3 Prius Technical Discussion' started by framistat, May 16, 2019.

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  1. framistat

    framistat Junior Member

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    Newbie here. Been looking for a good used late 2014 to 2015 Prius for several months now.

    Found this one, body and interior are exceptionally clean, 35k miles, 1 owner, local trade, clean CarFax and Toyota service record - just regular oil changes. No collision damage verified by a local collision shop. Spare has been briefly used, four new tires on it. Test drove, rides well and tracks straight.

    Used Dr Prius to do a full battery diagnostic and lifetime test. The lifetime came in at 100.71% which is odd. Then the diagnostic gave poor balance on blocks 3,4,7,8,11,12 and 5,6,9,10.

    The dealer did a health check, but that was just running the engine for 5 minutes to get the charge from 64 to 67% and then taking a static voltage reading. I asked for a load test. (Maybe there's some policy not to do a diagnostic test for a prospective customer so as not to kill the sale?)

    I do have a question in to Jack about the threshold for the "poor balance" message.

    Your thoughts? It seems my choices are 1) take a chance on the car, since it is otherwise pristine; 2) walk away; 3) buy the car but also purchase a Prolong to recondition the battery.

    If it were you, what would you do? I am retired and can't afford to make an expensive mistake.
     

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  2. mjoo

    mjoo Senior Member

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    I'd choose option #3. If you could get a good deal on the car knowing you will spend money and time installing a Prolong Automotive harness and clean out the HV fan. With those low miles I'd also consider an EGR clean earlier than the 100k advice. I did mine at 70k and it was more than half blocked.
     
    framistat likes this.
  3. JC91006

    JC91006 Senior Member

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    Car battery is under warranty
     
  4. bisco

    bisco cookie crumbler

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    not until it throws a code, but your warranty is either 8/100 or 10/150. i'd go for it and skip the prolong.
     
  5. Dxta

    Dxta Senior Member

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    I'd choose #3, with or without the prologue system.
    I can work on the pack, alternatively, without the system.
    I could purchased hobby chargers, and do the job, if I can't afford the prologue charger.
     
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  6. framistat

    framistat Junior Member

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    Bought it tonite, the dealer is delivering it to my home on Monday. I plan to drive it for a few days and rerun the battery tests, maybe do that a few times to see if the blocks balance themselves out. The balance problems may have been from the car sitting in the lot. Thanks!
     
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  7. Grit

    Grit Senior Member

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    4) Run away. Battery packs doesn't balance themselves out, car engine doesn't run for 5 minute straight, SOC cuts off around 60% unless it was in warm up stage. Look up the expenses for a grid charger and HV battery, if you have that raining day fund already, then buy.
     
  8. JC91006

    JC91006 Senior Member

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    Since this is technically a used car, the battery might not even be original
     
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  9. mjoo

    mjoo Senior Member

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    The only way to know for sure is to compare the serial numbers on the battery modules.

    Pixel XL ?
     
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  10. Travis Decker

    Travis Decker Active Member

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    Why would you even consider worrying or messing with the battery with this age and mileage? It's covered. If you install the prolong it won't be covered by Toyota anymore so why would you touch it.

    Buy the car and drive it worry about the battery in about 2022, or do what I buy my clients to do, buy one with 20 to 30,000 mi on it and then sell it at 78,000 miles, least depreciation and you never need to worry about anything except for tires and oil changes....

    Just my .02
     
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  11. TMR-JWAP

    TMR-JWAP Senior Member

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    X100!!!!

    Thank you Travis, for saving me the time I would have spent writing the same thing.
     
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  12. Travis Decker

    Travis Decker Active Member

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    No reason to make it complicated! We are talking about the absolutely most boringly reliable car ever built!

    At my shop people come in with 170,000 mi on a Prius and a P0A80. I make the phone call "you need a new hybrid battery." "But it's expensive!" To which my reply is something like this "you probably bought this car new and have done four sets of tires three headlight bulbs and 34 oil changes it's been the best car you ever have owned right?"

    If you divide the cost of the hybrid battery over the miles the Prius is still the absolute cheapest car to possibly drive on the road. Don't worry about it if it fails fix it. They all fail eventually it is a battery, so budget 10 bucks a month or something towards the eventual "triangle of death"

    Maybe it's because in my former life I fixed European cars but a lot of prius owners take this fact for granted because they've been spoiled by a car that requires almost nothing.

    Boring is good just don't expect it to never break

    My car needed a hybrid battery at 280,000 and I will replace it again at 400-500,000 with a smile on my face because it's the cheapest car I've ever owned!
     
    Prieth, ASRDogman and RMB like this.