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Any possible damage driving with a faulty HV battery

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by zelium, Jul 10, 2014.

  1. zelium

    zelium Junior Member

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    As I posted in a different thread (Where to buy a genuine Toyota OEM HV battery | PriusChat), the HV battery in my Prius 2007 (140k miles driven) went bad and needs to be replaced.

    I have been reading many HV battery related threads here and might want to challenge to replace only faulty battery blocks and to re-balance the battery. FYI, I got two OBDII codes (P0A80 and P3017) and the code told me that the battery block 7 became weak.

    I have not yet decided whether I get the battery replaced as a whole at the dealer or challenge to the replacement of the faulty battery block by using the info posted here (Thanks ryousideways for a great thread). While I am contemplating about this, I am driving my Prius to my work and runs approx 10-15 miles a day.

    Sometimes, I have a situation that I cannot accelerate well and the engine RPMs stay around 3000 and my car was still sluggish like the car was in a low shift gear.

    Anyways, to make long story short, I am wondering if I cause any damage to Prius running in this way (driving 10-15 miles per day with a faulty battery). Should I not drive my car until the battery totally gets fixed?

    Thanks in advance.
     
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  2. jdenenberg

    jdenenberg EE Professor

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    The only problem is that if the HV battery gets too weak, it will not be able to spin the ICE and you'll need a tow.

    JeffD
     
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  3. zelium

    zelium Junior Member

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    Thanks a lot, JeffD. I have a road assistance included in my insurance and should have the number to call them handy. :)
    And could you by any chance let me know why high RPM, low shift gear problem happening? Is the Prius trying to charge the battery? I am just curious.
     
  4. The Electric Me

    The Electric Me Go Speed Go!

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    The car operates as a system. Hence the term Hybrid Synergy Drive.
    You probably haven't done any permanent damage, but make a decision and get it fixed.

    Operating any machine in a degraded mode, with a faulty but vital part not functioning properly is always a bad idea.
     
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  5. zelium

    zelium Junior Member

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    Thanks for the advice, The Electric Me. I will try not to drive my Prius now on.
     
  6. jdenenberg

    jdenenberg EE Professor

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    Your Prius has two power sources and one of yours (the Battery/Electric Drive)is weak so your ICE needs to rev up to supply all of its 98 HP to get your Prius moving without the assistance of the electric drive.

    JeffD
     
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  7. dorunron

    dorunron Senior Member

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    zelium

    Basically you are over working the ICE since the battery is weak and failing. Do as other's have suggested. Either repair the battery or replace it. Eventually your Prius will run no more. I am sure your dash is already lit up. That should be telling you something... There is a reason for the red triangle and the CEL light. Fix the durn thing. You have a great car there, it just needs some TLC.

    Ron (dorunron)
     
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  8. zelium

    zelium Junior Member

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    Thanks for the clarification. I appreciate your response.
     
  9. zelium

    zelium Junior Member

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    Ron, thanks for your comment. I stopped driving it expecting that there should be no more harm done on the car. I still have not decided which route (fix at the dealer or DIY) I would go. I took your advice seriously and will make a decision pretty soon.

    zelium
     
  10. Patrick Wong

    Patrick Wong DIY Enthusiast

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    1. The Prius gasoline engine with Atkinson cycle is highly fuel-efficient, but has poor low-end torque. MG2 powered by the traction battery provides this low end torque to the power train. If the battery is failing, MG2 won't provide much power so the engine has to spin up in an effort to compensate - and the result is poor acceleration.

    2. I don't think you have to worry about causing more damage but it is not particularly safe to be driving a vehicle with degraded acceleration capability and you'll eventually be stuck at the side of the road. So I agree with the others who suggest you should decide upon a repair strategy and execute it so your car will be restored to normal performance.
     
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  11. zelium

    zelium Junior Member

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    Patrick Wong,

    Thanks for your information. I have been driving Prius for more than 7 years but I have not known that much information until now. In fact, I learned a lot from the battery problem I have. I don't know when, but my next car will be Prius again, so all the information I get now is so valuable. I really appreciate your comment.