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Question about hybrid battery

Discussion in 'Gen 2 Prius Main Forum' started by CaptainDan, Jan 22, 2021.

  1. CaptainDan

    CaptainDan New Member

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    Hello! I am not a Prius owner but I am thinking about buying a 2008 Prius Touring. It has 132,000 miles and is being sold for $5,000.

    I know very little about Priuses and I learned today about the hybrid battery, namely that it is much more expensive than a traditional car battery. Anyway, the dealer that is selling the Prius explained that they refurbished the original battery. The original cells are all the same, and the dealer said that they are charging well and working fine. But they replaced the HV hybrid battery wiring harness. I think this is what they meant by a refurbished battery.

    Basically, I'm wondering if this seems like a big risk to buy the car, knowing that the hybrid battery is still original, except for the wiring harness. The dealer explained to me it's not really possible to estimate how long the battery could last for, and that they have a very large range of life.

    I also read that the biggest killer to a hybrid battery is inactivity, such as leaving the car sitting for over a month without using it. The dealer confirmed that but said he had no info about whether the car had been inactive like that before with previous owners--which is understandable.

    Any thoughts?
     
  2. TMR-JWAP

    TMR-JWAP Senior Member

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    There are a couple ways to evaluate the HV battery prior to buying a car. There's a handful of apps available for your phone that can display module block voltages. The apps can even help you perform a battery test. You can even use the AC system to test the battery since the AC compressor runs off battery power. Don't forget to also check the brake system actuator/accumulator, as that can be an expensive repair also. Press the brakes 2-3 times until you here the brake pump start and immediately let go of the brake. Leave your foot off the brake and see how long it takes before the pump starts again. A GOOD pump will make you die of boredom waiting. If the system is leaking internally, the pump may start in just 10 seconds. Even 5 minutes, to me, is too soon, but could last for years of use.
     
  3. mr_guy_mann

    mr_guy_mann Senior Member

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    Kudos to you for performing research BEFORE purchasing a Prius. As mentioned the high voltage battery or the brake accumalator are some of several known problem areas on Gen2 Prius. Others are the Combination Meter (speedometer) not turning on, failure of the inverter coolant pump and or the "heater" control (3 way) valve. Most of these problems do not happen to every car (at least not all at once). It is a good idea to have any used car inspected by your mechanic - preferably one with some hybrid experience.

    Realistically the safest bet is to budget for the possibility of having to replace the hv battery in the next year- the original pack might last 5 more years or it could fail next month. If you want the car to be reliable then the best option is new battery modules. That would be around $3000 or more if a Toyota dealer installs it, to under $2000 if you were able to install them yourself (either Toyota or NewPriusBatteries.com).

    That should give you 5-10 years of no worries about the hv battery. Anything else is a rebuilt or refurbished hv pack made of USED modules that may or may not have been cycled (discharged then charged several times to try an restore capacity) and matched. Refurbs might last a few years or a few months- they don't have a good track record.

    Another thing to consider is that in quite a few parts of the world, theft of vehicle catalytic converters is an increasing problem- and the Gen2 Prius is a prime target as the cat can be quickly cut out and is high value to a recycler. You can read through the Gen2 forums for everything mentioned here.

    The Prius can be a very good car, but you should have awarenes of what COULD happen if you own one.

    Posted via the PriusChat mobile app.
     
    #3 mr_guy_mann, Jan 23, 2021
    Last edited: Jan 23, 2021
  4. royrose

    royrose Senior Member

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    Actually, your dealer seems knowledgeable and honest. Is it a Toyota dealer? If so, what would they charge to replace the battery if it goes out? Maybe you could get them to agree on a reduced charge for the labor to install when/if needed.

    As TMR-JWAP says, there are apps to test the hybrid battery. You would need an OBDII bluetooth adapter that plugs into the diagnostic port under the dash. I use the Dr. Prius app with an OBDLink LX which is about $50 on Amazon.

    Hybrid battery diagnostic and repair tool for Toyota and Lexus
     
  5. CaptainDan

    CaptainDan New Member

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    Thank you all for your thoughts and suggestions.

    @royrose it is not a Toyota dealer, but thank you for the suggestion.

    To be honest, a lot of this stuff is a little over my head, at least for the urgency of the situation, just because I need to buy a new vehicle as soon as possible. I am thinking about bringing it into a mechanic that specializes in Hybrids to have them inspect it. I had brought it to my mechanic yesterday but in learning more about the uniqueness of a hybrid it might be good to bring it to someone who specializes in hybrids.
     
  6. bisco

    bisco cookie crumbler

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  7. Moving Right Along

    Moving Right Along Senior Member

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    For any used car, the biggest factor to consider is how well it was taken care of by the previous owner(s). If it comes with the maintenance and repair history, look it over and see if it’s been regularly maintained. If so, you’ll probably get a good car with minimal problems. If not, it’s a greater risk.
     
  8. PandaPanda

    PandaPanda New Member

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    I am no expert, I still use my 2008 Prius. I really think it comes down to maintenance of the vehicle and if they can show proof if it.