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HV Battery Failing

Discussion in 'Gen 2 Prius Technical Discussion' started by magruder, Sep 25, 2009.

  1. Flying White Dutchman

    Flying White Dutchman Senior Member

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    i was the first:cheer2:





    j/k
     
  2. magruder

    magruder Average Member

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    Agreed:first:
     
  3. magruder

    magruder Average Member

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    One more question, since I've never driven a Prius with a newer battery. I was driving about 10 miles mostly uphill. The SOC went to one bar and stayed there is that normal? The SOC doesn't go to green anymore, but I assume that is because I have normal capacity now.

    Thanks,
    Dave
     
  4. efusco

    efusco Moderator Emeritus
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    I very rarely see one bar, and almost never when actually driving (usually if I'm stuck in traffic for extended times of inching forward on battery only), but I wouldn't call it a problem if everything else seems to be operating normally unless you see it frequently in places you've never seen it before. The car may be recalibrating itself.
     
  5. statultra

    statultra uber-Senior Member

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    I think you need to take the car on a long drive with cruise control. I used to take my Prius on short trips, and noticed my battery always stayed below 4 bars, and hit one bar immediately after startup with the a/c on. A week later i took it on a long trip +40 miles everyday for 2 weeks and my battery always stayed above 4 bars.

    Unless you want to manually charge it up to the green and shut it off leave it overnight. Put the handbrakes on, and put it in drive with your left foot firmly on the brake, and press on the accelerator fully, this will charge the battery fast. I suggest you do this on a empty road or parking lot.
     
  6. magruder

    magruder Average Member

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    Thanks,

    The battery seems to be performing perfectly. I make that trip about once a week, so I'll see what happens next time. The SOC generally stays in the mid range otherwise so far. I will switch back to the 2007 ECU when I have time.
     
  7. magruder

    magruder Average Member

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    Thanks,

    I keep an eye on the SOC, as I have a 90 day warranty from the salvage yard. I just want to make sure I bought a good battery.
     
  8. lunchboxjo

    lunchboxjo New Member

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    Re: HV Battery Failing due to

    ...so is it very important to replace the ECU when replacing the HV battery? also I have to ask if it is terribly difficult to replace modules? I mean is the operation involved past a socket set and a like a chilton's manual or do you need a subscription to a technical website?

    I have an 01 Prius and my throttle body went out. The dealer service told me this caused a malfunction in the HV battery. I picked up codes for cells 6 & 10 on a personal OBD scan. So Toyota motors has told me they will compensate $1k on the $4k bill to replace the throttle body, and the HV battery, or they can put that towards a trade-in.
    I still owe $5k on the loan and it's valued at $72000.

    So what do I do?

    I'm an amateur handy man for frugality. However, If I pay the $3k to have the warranty I'm covered for another 8 years or 100k miles put on the HV. I'm really confused.

    Please let me know any suggestions.
     
  9. efusco

    efusco Moderator Emeritus
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    Re: HV Battery Failing due to

    ??? I have no idea how the HV battery could be related to the throttle body...makes absolutely no sense to me and I would NOT repair or replace the battery unless and until they can clearly explain why you should and how there could possibly be a relationship. I suppose it's possible that b/w the mechanic, the service rep, and you that there's some misinterpretation, but if not it sounds like you might be getting 'squeezed'. I can believe the throttle body could be bad as many have been on the 1G Prius, but I'm much more skeptical about the battery.

    *aside--how do you own $5k on an '01?

    It is not recommended to replace individual modules in most cases as they can be unbalanced. They need to be age and charge balanced and that can get tricky. Not impossible, but tricky and it certainly involves some risk. If you mean replacing the entire battery pack, that's much more of a DIY project. The ECU does not need to be replaced unless it is bad, but it may come with any salvage battery you obtain.
     
  10. magruder

    magruder Average Member

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    Re: HV Battery Failing due to

    If you do need a new battery, it is not that difficult to replace. I wouldn't even mess with individual modules, since salvage batteries are sufficiently inexpensive. The ECU is easy to replace as well.
     
  11. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Re: HV Battery Failing due to

    This statement might be causing part of your confusion and indecision. In fact, if you pay $3K to replace the traction battery, the new battery will be warranted for one year, under the same warranty that applies to any new part installed by the Toyota dealer.
     
    1 person likes this.
  12. Sandy

    Sandy Hippi Chick

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    i have a new traction battery if anyone needs it, if anyone need it and can afford one please send me a message
     
  13. rfelley

    rfelley Junior Member

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    Don't know if I'm breaking the rules by saying this, but I have a 2005 recent wreck in my shop (my daughter ran it into a power pole Aug. 25, 2009). I've been concerned that the HV battery is wasting away by not being in use. I'd be willing to make a reasonable deal just to see it get back into service. Dial me up and let's talk. Rich (503) 812-2229.
     
  14. lunchboxjo

    lunchboxjo New Member

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    I'll give you a call Rich, but I'm not sure if I need the battery just yet...

    the dealership told me I have two dead cells due to the car only running on the battery, since the throttle is stuck.
    I don't know if I should believe this or not so I'll follow the symptoms... so the dealership wants 4k to replace the throttle body and battery and Mr. Wong was right, Toyota will warranty the new battery with only one year manufacturer's warranty ___bummer__...but I'll just DIY it and see where it takes me.

    Does anyone know how to clear codes on a 2001 Prius?
     
  15. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Note that Rich's car is 2G. That battery will not work on Classic since the Classic battery has 38 modules while 2G has 28 modules. Now, if you get two 2G batteries with 56 modules, then in principle you may be able to pick 38 of those and install in the Classic battery case, subject to possible issues with SOC charges between the modules coming out of the two battery assemblies. Another poster recently did this and it seemed to work well although he may have had to work on the sheet metal enclosure for fit reasons.

    The reason that this makes sense for Classic is because Classic salvage batteries are not easy to find and are relatively expensive, while 2G salvage batteries can be purchased for around $400 each (or less) plus shipping. Why pay $1K for a Classic battery that is ~8 years old?

    You can clear most codes by disconnecting the 12V battery negative terminal for several minutes.

    Before you replace the throttle body I suggest that you try cleaning the dark gunk out of the throttle body interior and throttle plate. You can rotate the spring-loaded throttle shaft by hand when the car is IG-OFF, so that you can clean the throttle plate underside.

    Maybe the correlation between the throttle body and the traction battery is as follows: the gasoline engine refused to start because of a throttle body problem. After repeated attempts to start the engine, the traction battery became depleted and two modules failed. This is just a guess.
     
  16. magruder

    magruder Average Member

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    So I returned my old battery to the dealer, and they are going to pay me $150 for it. I'll believe it when I see the check, but I got a written promise from the Service Foreman. That brings my battery cost down to $250, and I still have the computer to sell. The newer battery is still working great and seems to have brought my mpgs up about 2mpg.
     
  17. Politburo

    Politburo Active Member

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    Doesn't Toyota provide a $200 refund for old batteries?
     
  18. magruder

    magruder Average Member

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    That is true, but the dealership wants to make something on the deal, so they keep $50. At least that is what my closest dealer does.

    (Edit: Well I thought you were in Colorado, must have been reading my own stats)
    Since you are in Colorado, I'll put in a plug for Grove Toyota on Broadway in Littleton. I thought I would have to ask for the fee, but they offered it right up. I have had good experiences with them in the past as well. I had a Land Cruiser and both keys stopped working, so I had to go in to get originals made off the VIN number. Grove made two new keys for me, and charged me $0 for it.
     
  19. magruder

    magruder Average Member

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    I did get the $150 from the dealer, so the battery cost me only $250 net. Also, I kept the old battery computer to sell, but I don't know what I'll get for it.

    Dave
     
  20. UKCLASSICPRIUS

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    Sorry to tread on your topic, & this is my 1st post, I would open a new topic, BUT all thats listed here, most concerns me, & I DID try using the search feature before asking silly questions:

    I have a classic prius 2001, BUT am in uk, I am having traction battery problems from this car the reverse has just about stopped working, & i am sure i need a traction battery repaired!

    I am being offered a 2004 gen 2 battery for 250 gbp! but only 28 cells & or a 2001 classic gen 1 battery for 75 gbp with 38 cells of which needs attention & apparantly has some dead or weak cells!

    Which way do you suggest I go? parts are really hard to get for the prius here in UK, Espacially HV batterys!

    Please advise...