free IMA update for HCHII 2006-08 from American Honda

Discussion in 'Honda Hybrids' started by hunter44102, Jul 30, 2010.

  1. Dream'R

    Dream'R Well-Known Member

    As other Canadian owners have reported, Honda Canada has now issued the same "product update" for 2006-08 models, as was previously done in the US.

    From my understanding of the problem, certain owners operate their cars in conditions that are "a perfect storm" so far as overheating the IMA battery pack. When you encounter high ambient temperatures the pack will already be above ideal conditions. The cooling system for the pack utilizes air from the car's interior which may already be extremely hot. Then when you add frequent engine restarts, electric-only air conditioning during auto-stops, recurring IMA assists following frequent stops and low SOC levels, we now have additional internal heat generated within the IMA battery which cannot be dissipated nearly fast enough.

    While my own car is rarely operated under such extreme conditions, I am planning to have the updated software installed. I drive using moderate hypermiling techniques most of the time so some loss of "assist affinity" will not bother me.

    Thanks to everyone who has shared their experiences already. It's too bad that some owners are now dealing with already deteriorated battery packs that haven't "thrown an error code" yet and are finding Honda unwilling to take their issues seriously. The more publicity these issues receive, the better the chances will be that the truly defective battery packs will get replaced under warranty.


  2. rhwinger

    rhwinger Well-Known Member

    I'm in line for the S/W update at the dealer Friday.

    Msantos, if you remember our conversation, I had a new IMA battery installed in the Feb/March time frame. Sorry, I just don't have the paperwork handy.

    My question is do you know how this latest S/W update compares to the S/W update recieved with the new IMA pack?
  3. msantos

    msantos Eco Accelerometrist

    Hi Bob;

    What I can tell you (with a good degree of certainty) is that among all the software revisions we've been getting since 2006, this most recent revision is not only the most comprehensive, but in my view, the most helpful as well.
    Truly a "must have" for most HCH-II owners and in your case, still a significant improvement over what you got at the time of the pack's replacement.

    On a related note:
    We should also be cautious/skeptical of the spin perpetuated by the media concerning the applicability of the most recent updates to the 06-08 model years only. As we look carefully at the data, this is certainly not always the case as many 09 owners are actually not better off than owners of prior model years. Their symptoms and reported incidences of severe recalibration episodes are right in line and sometimes worse than what the 06-08 owners report. :eek:

    Sure the 2009's come with improved software governance that is better then the factory baselines of the prior model years, but many 2009's will also benefit from the latest updates as well. As the latest optimal baseline, it is after all meant for them too even though the official word is that they are magically excluded.

    As far as I know, only the most recent 2010 models possess the most optimal baseline of the software.


  4. rhwinger

    rhwinger Well-Known Member

    Thanks MSantos. I've been reading other owner's responses and was a bit concerned. I'll submit my impressions after the install.

    BTW, I replaced the OEM Dunlops with the Michellin Energy Saver A/S's. While the numbers have gone down a bit with the new tires, the ride comfort and quietness has definitely gone up! The numbers are slowly getting better, though.


  5. Mendel Leisk

    Mendel Leisk 2010 Prius (CAN Touring) Staff Member

    Ok, got our software updated today, theoretically. As I've been going on about: I still wonder if we didn't get the update 2~3 weeks back, when the car was in for mechanical work. Upon picking the car up that day I noticed a change in behaviour: slightly more miserly assist, and higher displayed state-of-charge. I wasn't looking for something like that, but it caught my attention. Since then I've gotten used to the "change" if there was any.

    Well today, my wife got back with the car from the "update", just about the time I got home, so I took it for a spin 'round the block. I could feel/see no change. Assist is there when you need it, even light pressure will show one~two bars assist. Coast and you see regen,. Not seeing anything untoward in a quick spin. Pulling into the garage state-of-charge was showing one shy of full, fwiw.

    For both the last two mechanical visits, and today's update we've got zero documentation. I will try to get that sorted tomorrow, and will post anything relating to the update (if I ever get the paperwork).
  6. Harold

    Harold Well-Known Member

    Thanks, Mendel. H
  7. Mendel Leisk

    Mendel Leisk 2010 Prius (CAN Touring) Staff Member

    Drove it a bit more today, but really haven't had an extended drive, just a few chore running kilometers. State of charge got down to 4 bars at one point, and it seemed like assist was getting held back or totally supressed at that state. I turned a few corners and got no assist showing. So, I do think something is different, in the how-and-when of how it reacts to diminishing charge state. I sense something is different but no big difference noticed.

    Put another way, if I didn't no something had happened, that the software had been revised, I might not notice it ;)

    BTW, I posted a crummy scan of the bill, and typed it out as well, over in MSanto's thread about latest updates:

    There are a lot of people posting regarding big issues, after getting the update. All I can surmise is it may depend on the state of your battery. Our's is no great shakes, it does recal fairly frequently, but it's ok for the most part.
  8. rhwinger

    rhwinger Well-Known Member

    First 31 mile segment today - 67 mpg this morning. Just about what I was getting before the update. I was getting in the mid 70 mpg range last summer, before the pack was replaced about March this year. New tires installed late June, only 44 PSI right now.

    I don't see a major FE change, but it did seem to drive a little "smoother"? Kind of hard to describe - probably just in my head.


  9. Mendel Leisk

    Mendel Leisk 2010 Prius (CAN Touring) Staff Member

    I'm not noticing a difference in mileage either, though with us it's "one man's ceiling is another man's floor", but we try ;)

    One difference, in a decent sunday drive: occasionally I would get no assist with modest acceleration, where I likely would show 1~2 bars in past. And it wasn't missed, ie: got along fine without it.

    I've been noticing, and heard mention, that various behaviours, re-cals and cessation of Auto Stop for examples, are happening with more state-of-charge bars showing. This, coupled with Honda's statement that state-of-charge display was going to be shown more "realistically", has me thinking: there's no real change there, state-of-charge when these behaviours occur is the same, just the displayed S-O-C is higher.
  10. ematzen

    ematzen Well-Known Member

    The only real change in State of Charge that I have noticed is that when it drops to 2 (what used to be dropping to 0) and does a forced recharge, it still allows for some electric boost (though you really have to punch it, but it is needed when starting from a stop on a hill, etc), whereas before when it dropped to 0 there was absolutely no boost available.
  11. hunter44102

    hunter44102 Well-Known Member

    agreed! I don't have the 'what the heck' moments anymore when I hit the gas and not only is there no assist, but it seemed like the regen (and A/C) would steal all the power at the same time. It doesn't seem to happen anymore. Great job Honda!
  12. rhwinger

    rhwinger Well-Known Member

    The drive home yesterday was not good. 95 degrees and I'm trying to be easier on the pack, so I ran A/C set at 85 degrees, low fan speed. At first, all was well trying to maintain SAHM on the interstate 55 - 60 mph. Battery seemed to hang in there mid level plus one or two bars, 63 mpg or so.

    Had to stop and pick up my son. Parked the car and in a few minutes we headed out of the parking lot to a traffic light. Light turns green, and I try to get moving. I apply the usual gas pedal pressure, engine RPM's to 1500 or so, but the car is just barely moving - I mean even for ME - barely moving. :eek: The SoC dropped to 2 bars like real fast. 3000 RPM and the car is still barely moving? I dump the A/C and check the rear view, thank God no one behind me. For the next 6 to 10 miles the car is sluggish but getting better. Got home with the last 12 miles of that segment and SoC was still pretty low around 4/5 bars.

    I called the dealer and then Honda America. I have a case number now.

    The Honda representative on the phone was very understanding and willing to listen. She also mentioned that if other drivers were experiencing problems, call Honda America and let them know.


    Last edited: Aug 31, 2010
  13. dlister70

    dlister70 Active Member

    I've had several drops of the battery power in the past few days. Today was the first time it dipped down to zero instead of one bar. I assume the air conditioning is eating up the battery when in auto stop.

    Today I was at 4 bars and was in line at a fast food drive through so I shifted to neutral and shut off the engine. When I started it back up, I went straight to zero bars. :(

    It looks like I'll be making an appointment to get the software update. I'm glad to see that it should be free..
  14. Mendel Leisk

    Mendel Leisk 2010 Prius (CAN Touring) Staff Member

    Just a few more observations, post update. For the record, it was doing a fair number of recalibrations before update. Anyway, having gone for a 80km~ round trip:

    1. State-of charge very persistantly holding at 4 bars, regardless of assist and recharge. It's very hard to budge it higher.

    2. It started out with a recalibration for the first few blocks, a continuation of one that started yesterday just before shutting down.

    3. Saw several instances where it was at (the usual) 4 bars state-of-charge, but refused to provide assist on starting out, as if it was in a recal.

    4. Also saw one or two instances where it did not regen when decelerating, even though the state of charge was at the proverbial 4 bars. Pre-update I'd only such behavior if state-of-charge was displaying 10 bars.

    5. In one instance, soon after the recalibration more-or-less ended, the state-of-charge reluctantly climbed maybe to 5 bars, then suddenly jumped to full.

    All of this leads me to believe one of the following is happening:

    a) The state-of-charge, and the computer's reactions to SOC, is much different. post update.

    b) The state-of-charge is being displayed inaccurately, or at least very differently, post update.
    Last edited: Sep 20, 2010
  15. dlister70

    dlister70 Active Member

    Today after leaving work I dropped from 4 bars to 2 as soon as I left the parking lot. I have not yet dropped below two bars after having update installed last Thursday. When I was driving home with the 2 bars, the car acted the same as it did when it would be at 0 or 1 bars prior to the upgrade. I floored it and got no assist, and I couldn't get more than 2 bars of charge even when braking.

    Hopefully it's a change in the way the system reacts, and not just a change in how many bars are displayed. :)

    I mean, if it won't let you drop below 2 bars, I would think that it would be good for the battery to not let it drain down. I drove in S for awhile to charge the battery, and it suddenly went from 5 bars to 8 skipping over 6 and 7.

    The jury is still out. It definitely acts differently, but whether it's good or bad, I'm not sure. :)
  16. ematzen

    ematzen Well-Known Member

    My experience is that it is a change in how many bars are displayed. When I start the car after sitting, per another post here, the conventional starter motor powers up the car. The SOC drops to 2 immediately.

    Yesterday, I immediately shut the car down after this happened (I video taped the start, to provide further documentation for Honda NA). When my wife started it 1 hour later, the conventional starter motor powered the car up again, even though we were at 2 bars on the SOC. That leads me to believe that 2 bars SOC = 0 charge in the battery. In my opinion, this means the update is intended to dupe people into believing that the battery is never empty.
  17. rhwinger

    rhwinger Well-Known Member

    My first full tank after the "update" came out to a dissapointing 56 mpg. I know my commute has changed a bit, and new tires not quite pressed up to max. But still, most of my segments were indicating 60 - 64 mpg, with occasional spousal use knocking that down a bit. Mileage seems to have taken a significant hit. :-(


  18. Is there a way to tell if you have the update or not? I just got my '08 HCH-II 2 days ago as a certified used honda. They gave me all the service documents performed starting with the certified inspection. I didn't see anything that looked like they updated the IMA.

    If I call the dealer service department and give them the VIN, can they tell me if it's updated or not?
  19. Harold

    Harold Well-Known Member

    Had the latest updates and I can not notice any change other than the CTV seems to be more sensitive? I am still very pleased with my HCH2:D H
  20. hunter44102

    hunter44102 Well-Known Member

    In the new update, the charge level should not get below 2 bars with regular driving. I think all the older software's would sometimes drop to 0 bars

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