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Is this really the hybrid battery going bad?

Discussion in 'Gen 2 Prius Main Forum' started by Curtanu, Mar 15, 2017.

  1. Curtanu

    Curtanu Junior Member

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    Two questions, for you who are "in the know": (1) does this indeed sound like a main battery going bad? (2) what options are there for replacing/fixing that battery?

    I've got a 2005 Prius which has been having some odd intermittent problems. As of 3 days ago, it now has a consistent problem and won't drive.
    General history:
    The car was rebuilt after 2 collisions, already in 2005. I bought it in 2015, and drove it without problems for 17 months. Current mileage is 153K (the last 20K are mine).

    Problem history:
    Late November, I was driving and suddenly dashboards lights came on & I lost all power. Lights on were: CEL, (!), VSC. I coasted & parked. Waited a minute. Restarted -- no problem. Drove 2 blocks to a gas station. Started again -- it started, but drove only with sputtering. Had it towed to Toyota dealership. Their report: "There is no CEL light on now. We see no codes other than an O2 sensor. It drives fine. There is no problem. That'll be $115." I then drove it (no problem driving) to an independent mechanic, who replaced the O2 sensor, but could find no other problem; his guess: maybe a bad ground somewhere.

    Drove with no problem until late December. I had driven 40 minutes, parked 2 hours, then when I tried to start it, the same lights (CEL, (!), VSC) were on. After many attempts, it did start; I drove several blocks with it weak & sputtering, dying at stop signs. Parked. Maybe 30 minutes later, tried again. It started and had only CEL on. It drove, a little bit weak at first, but soon seeming almost normal -- maybe a little bit of engine racing. After a week, I took it to a very well-respected local mechanic shop, who found an assortment of error codes, with no apparent logic: P0A7A (generator inverter performance), B1421 (solar sensor circuit), B1423 (a/c compressor -- but there is no a/c anymore - from the damage in 2005 - so of course this error will always be present), B1790 (airbag sensor ECU communication), and each tire's pressure sensor. There were no warning lights on, at the time. Their conclusion: "We can't tell; bring it back in when the lights are on."

    Drove with no problems until late February. Then started having intermittent occasions with the CEL on, but car would drive seemingly without problem. Then March 2, the lights came on while driving (still had power, drove fine), so I went back to mechanic shop being careful to not turn off the engine -- thus still had the lights on. They briefly read the codes and said: "Same array of random codes; we can't tell what's wrong; maybe it's a computer communication problem deriving from being a rebuilt car."

    Drove it a few times, no problems. Then March 10, it died. Drove it into town (40 minutes) no problem. Parked for maybe 90 minutes. Tried to start: same three lights on: CEL, (!), VSC. But now it is consistent behavior. It starts fine, but within a couple seconds, the engine kicks on & instantly the 3 lights come on, and the car shuts off power. If I work at it, I can quickly get it into Drive & get a touch of forward momentum; then it will keep driving but only weakly and with much sputtering. Actually, at first, I drove it 5 blocks, parked, shopped briefly, then started it again. The 3 lights were on, but again if I quickly got it in Drive and moving, it kept going. I drove for a few minutes -- but the engine was racing. Then it lost acceleration, though it would maintain its speed at 27mph. That seemed kinda bad. So I pulled over, stopped. It would not go again. Since then, the same behavior: the 3 lights come on when the engine kicks in, which always happens a couple seconds after powering on; it has at best sputtered 1 block distance. Had it towed back to the same mechanic shop. They now report 3 error codes that lead them to believe it is the hybrid battery having problems. In the HighVoltage ECU, it shows P0A1D, P0A7A (note that this one had shown previously, in January: "generator inverter performance"), and P3000. In the Cruise Ctrl module, it shows the same 3 codes. In the HighVoltage Battery, it shows P0A80.

    For fixing it, under the theory that it is the battery gone bad, they found a reconditioned full battery assembly, to the tune of $2200. Or to diagnose the existing battery, they're saying about $500 to diagnose it -- pulling apart the battery & checking individual cells. But I may have caught a break [if I want to even get it fixed] in that one of the techs there has a friend who does this, so they could do individual cell replacement for me -- and I've have a trustworthy local shop standing behind it, instead of just a random person from Craigslist.

    Possible causes:
    (1) The battery is really going bad.
    (2) Water. There is a leak in the roof (the passenger side, top corner of the hatchback). It's Washington. It rains here. This past week, the leak seemed especially bad; there is now standing water around the 12V battery, also a little in the spare tire compartment. Who knows where else. So that became my theory -- that the water was causing some kind of weird electrical behavior. But the shop didn't find water elsewhere. (And around the the base of the 12V shouldn't really cause any problems.)

    If it is (1) the battery -- then why didn't any of the 3 shops (inc. one Toyota dealership) find anything about it, previously? And in particular, does the behavior leading up to today fit with the battery-gone-bad theory?

    Upon reflection, I'm inclined to believe it is the battery, after all. One observation might fit esp well with that -- or so it seems to me: when I visit my brother, I must go in reverse in order to climb his very steep graveled driveway [Thanks to the design decision at Toyota to cut the power when the tires slip -- with no means of overriding that behavior. So if I try to drive up forwards, the front tires slip on the gravel, cutting power, and I'm stuck. But in reverse, I can drive up.] Anyhow, point is this: the first time I did that, the Prius zipped right up the hill in reverse - nice as you please. But every time since then [not very often, maybe 10 times total], it has gotten increasingly sluggish at the maneuver. The most recent time, it didn't make it up at first, but I had lots of cargo. I had to first unload the heavier items; then it could go up. And the last 3 or 4 times, I had to keep the petal to the metal, to make it.

    Some additional tidbits of data:
    + The 12V battery died June 2016. I replaced it myself (did I have a choice, stuck 40 minutes from town?) with an Optima battery.
    + The right headlight constantly flickers. Bad ground?
    + There was exactly one time (May 2016) an actual spark from under the dashboard. As in, I was driving, there was a bright white flash & zzzzap sound. But no warning lights, no problem driving, nothing. Weird. Mechanic couldn't find anything there, other than the fuse box was dangling loose from its tie-down.
    + MPG has been consistent: 44-46 during winter and/or 70mph highway speeds; 49-51 during summer and/or slower speeds.
    + Mechanic shop (only the 3rd one, others didn't notice I guess) reports that the computer in the car is actually a 2006 computer (vs a 2005 car).

    So there's my story. Whaddya think? Sound like the battery?

    And the second question is short: if it is the battery, what options are there to fix/replace it?

    Thanks in advance!
     
    #1 Curtanu, Mar 15, 2017
    Last edited: Mar 15, 2017
  2. fotomoto

    fotomoto Senior Member

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    Get the codes.
     
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  3. Curtanu

    Curtanu Junior Member

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    I'll get the specific codes & add them here. However, part of my question is the larger picture: qualitatively, does it make sense that it's the battery -- does a failing battery behave this way? And simultaneously, does a puddle of water causing odd electrical currents make sense? And even: are the error codes trustworthy, given the rebuilt nature of the vehicle -- might it just be a communication problem between components & then the computer says, "Whoa! I can't talk to the XYZ module! Something is wrong. I'm shutting the car off!" ?

    In any case, I'll get the error codes & report them here.
     
  4. bisco

    bisco cookie crumbler

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    welcome!
    i suspect something in the one of rebuilds has gone bad. maybe ground as someone said early on, possibly a wiring harness issue.
    could be very difficult to find.
     
  5. Curtanu

    Curtanu Junior Member

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    OK, I got the codes that are now showing.

    In the HighVoltage ECU, it shows P0A1D, P0A7A (note that this one had shown previously, in January: "generator inverter performance"), and P3000. In the Cruise Ctrl module, it shows the same 3 codes. In the HighVoltage Battery, it shows P0A80.

    I will update those in the original posting, as well.
     
  6. Curtanu

    Curtanu Junior Member

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    Thanks... so you don't think the symptoms fit the battery going bad? (Or perhaps, the wiring problem has *caused* the battery to go bad?)
     
  7. JC91006

    JC91006 Senior Member

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    P0a80 means replace hybrid battery. Tackle this first and see if other errors go away
     
  8. bisco

    bisco cookie crumbler

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    fyi, you can buy a new toyota battery for the low $2,000.'s or a rebuilt between $500 and $1,400. labor not included. be careful with rebuilds, they can be iffy.

    also, you may need to go back to toyota with the codes, or a mechanic who specializes in hybrids and has toyota specific troubleshooting software.
     
  9. Curtanu

    Curtanu Junior Member

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    Oh! Then, that's a pretty blunt error code! :) But there remains the question: is that really the problem? In other words, do I want to spend possibly upwards of $2000 to replace the battery? If the problem really sounds like its a wiring error in the rebuild -- then I'd be wasting $2000+. But, if the symptoms do indeed match the general picture of a failing battery, then it would make sense to believe that blunt error code.

    And then there's the question of what options are there for replacing/fixing the battery?
    Buy a new one from Toyota dealership: $3300 and change.
    Buy a refurb via my local auto shop: $2200
    Buy a refurb from eBay: approaching $1000, including shipping. But then I'd have to install it. Guess I could read up on how to do that.
    Get the current battery fixed up with some new cells, at my local auto shop: price not yet stated, but probably around $1000.
    Learn to replace the individual cells myself: probably not practical, whatever the savings.

    Other options???
     
  10. bisco

    bisco cookie crumbler

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    sell it and buy a corolla or something?
     
  11. Curtanu

    Curtanu Junior Member

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    Thanks... my local Toyota dealer quoted $3300 and change, inc labor & tax (with the caveat, "assuming the battery price is the same as it was back in December"). He said they actually get it from someone other than Toyota because "the warranty is the same, but it costs a little less". (So that's actually his price for a refurb, I guess.)

    Yes, the local shop (non-Toyota) is good, but don't specialize in Toyota or hybrids. Good point.
     
  12. Curtanu

    Curtanu Junior Member

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    Ha! Actually that's exactly what I'm thinking, as my alternative to sinking the money into this. A good ol' Camry stationwagon from the 90s might suit me fine. The Prius has such a low ceiling on the hatchback that I can't get much stuff in there!
     
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  13. 05PreeUs

    05PreeUs Senior Member

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    I'm VERY sure Toyota NA would deem the offer of a non-OEM battery by a dealer to a customer to be WELL outside of the playbook and given that new OEM batteries are in the $2000-$2500 range, they are high, W A Y high!
     
  14. Curtanu

    Curtanu Junior Member

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    Hmm. I'll try calling a different Toyota dealer tomorrow (too late today). The local one has been quite helpful in the past, with more minor things. Maybe I was dealing with somebody who didn't know what he was talking about; maybe I'll even try calling them again tomorrow & see if I get a different answer.
     
  15. Curtanu

    Curtanu Junior Member

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    BTW, I'll bet it could even drive up the hill to my brother's house!
     
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  16. bisco

    bisco cookie crumbler

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    it won't cut power to the wheels, that's for sure.
     
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  17. 05PreeUs

    05PreeUs Senior Member

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    ALL dealers are in business to make money, matter of fact, that is the primary reason everyone who works does so as well :)

    However, there are exactly two kinds of dealers and this starts at the TOP of the organization:

    1) Profit Max - get the most $$$ from every transaction you can

    2) Customer Max - get the most customers you can, treat them right and the $$$ take care of themselves

    We all need to decide which we want to and/or are doing business with and often it's not easy to tell.
     
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  18. JC91006

    JC91006 Senior Member

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    You have to believe. It's a duck
     
  19. Curtanu

    Curtanu Junior Member

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    Yeah, I reckon. But I was still questioning if it was quacking or hooting or maybe honking.
     
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  20. TMR-JWAP

    TMR-JWAP Senior Member

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    No offense toward you, but this sounds like one of those "slightly" wrecked but "completely and properly repaired by a local whatever" f*** jobs that got dumped on an unsuspecting consumer. It was only a matter of time before the jerry-rigged repairs(?) showed up..... Ditch the car, as it is most likely getting ready to become a money pit
     
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