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I have a P0A7F code which is a battery issue

Discussion in 'Gen 3 Prius Technical Discussion' started by gdlcolorado, Oct 14, 2010.

  1. gdlcolorado

    gdlcolorado New Member

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    My check engine and red triangle light came on. I checked the code and it's a battery issue. The code is P0A7F. I called the dealer and they want me to bring the car in for a check. Has anyone else experienced this problem?

    I'm afraid it will lead to me replacing the battery. I have about 117,000 miles on the car. They have a service bulletin open on this code but I may have exceeded the 100,000 mile limit.

    If I do need to replace the battery are there any improvements I can make in this area?

    Thanks,
     
  2. adamace1

    adamace1 Senior Member

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    If you have 117,000 miles on the car, i'm going to say you have exceeded the 100,000 miles limit.
     
  3. jayvee

    jayvee Member

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    I think you may have better luck posting in the Gen II forums.
     
  4. gdlcolorado

    gdlcolorado New Member

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    Right. But if anyone has had any experience here I would like their advice. As in the service bulletin was issued a year ago before I exceeded the 100,000 mile mark. That's the kind of info I'm looking for.

    Thanks
     
  5. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    A service bulletin tells the mechanic how to do a service, it is not a recall. It would not matter how long a mechanic has known how to fix a P0A7F, you did not have one until now.
     
  6. gdlcolorado

    gdlcolorado New Member

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    OK. I guess my line of thinking was if they knew this was an issue a year ago and I take my car to the dealer I may have a case. Thanks for the advice. I think this is a common enough problem that others have been down this road before me.
     
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    DTC P0A7F "Hybrid Battery Pack Deterioration"

    Either the internal module resistance is above spec or the SOC from one module to the next is larger than it should be. In either case, you are probably going to need a new traction battery although there is some possibility that the battery ECU has failed instead.

    I am not aware that a TSB exists regarding this. If you should find this to be the case please post the # (and ideally a .pdf copy, if you can get hold of one.)

    Since your car is out of warranty an alternative if you can DIY is to replace the battery with one purchased from a salvage yard. You may be able to buy one for ~$500 plus shipping, check eBay Motors. 2G salvage batteries are fairly inexpensive since most 2G are still under the hybrid system warranty. Good luck.
     
  8. seilerts

    seilerts Battery Curmudgeon

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    First of all, how did you read this code? Do you have, or have access to, a scan tool that can delve into the HV battery ECU and tell you the internal resistance of every module? {Can Scangauge do this? Or just Techstream and AutoEnginuity?) P0a7f is related to either high internal resistance of a module pair or poor capacity of a module pair. Reference range for internal resistance is 0.01 to 0.1 ohm. Your dealer will be able to read the internal resistances for all module pairs, although it is quite possible that no one in the service department will have ever seen this code and know what to do other than to follow the diagnostic flow chart and suggest that you buy a "new" traction battery for $2588 + labor.

    Also, is it possible that your 12V battery is dying and this is just one of those quirky things that happens? This particular code is NOT a fail safe (limp-in) code, meaning that you have a MIL warning but operation is not affected. So it is always worth clearing the code a few times to see if it keeps coming back.

    If you have to replace your battery, there are loads and loads of them in junkyards, for about $400, and by finding a fresh one you might be able to drop it right in. There are a few hybrid garages in Colorado and you might try calling them as well.
     
  9. chathud

    chathud New Member

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    Im having thw same issue .is there any worked around to resolve this
     
  10. bisco

    bisco cookie crumbler

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    you could test the individual cells and replace the bad ones.
     
  11. 2015ToyPrius

    2015ToyPrius Junior Member

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    If you decide to take the battery pack apart, check the individual cell connections for corrosion. If they are corroded, take the screws off and clean each one of them EDIT(and the connection strips) and reassemble and try it. This has been known to solve the problem with some battery packs. If there is no corrosions, then you either have to check each cells voltage and find the low voltage
    cells and replace them, or get another battery pack. If you get another battery pack, you can get one that has been rebuilt, for less than a new one. I know there is a Hybrid shop in Sri Lanka. You'll have to search for it, as I lost it's location. Wish I could help further. EDIT: If you do the job yourself, be sure to look on youtube for a video of how to do it, there are many. Also, clean the fan, and ducts.
     
    #11 2015ToyPrius, Apr 6, 2016
    Last edited: Apr 6, 2016