Clarity Issues

Discussion in 'Clarity' started by jdonalds, Dec 22, 2017.

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  1. fotomoto

    fotomoto Active Member

    No, it can and does. GM just didn't really promote that fact. But that's sort of besides the point. Once a pack is depleted, it doesn't have the "horsepower" of a full pack for the EV motor to draw from. That's why GM came up with mountain mode because the car literally would not climb a mountain pass on the ICE alone. Tesla 1/4 mile racing is done with full packs for a reason.

    Sounds to me, the car has also depleted the hybrid portion of the battery trying to maintain pace and now the 100hp engine is trying to haul a 4500 pound car up a steep grade at regular speeds and frantically trying to recharge the battery and power the a/c and..... Not gonna' happen.

    Try building up or saving some EV miles (I'd suggest half so there's no doubt) and try this route again. Report back.
     
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  3. MNSteve

    MNSteve Well-Known Member

    Just a quick $.02. I have not experienced the power loss issue, but I live in the flatlands. On the other hand, sounds like some of the incidents have been on flat roads.

    At one point in this thread the statement is made that the engine always drives the wheels at speeds over 45. As those of us in search of the elusive gear icon know, that's not the case.

    I consider this a serious safety issue. I've seen suggestions to maintain charge in the battery to prevent this situation. While I agree with that idea, it is not a general solution to the problem. This car was designed to be driven by someone totally ignorant of PHEV aspects, so suggesting a technique that requires pre-planning and knowledge of the inner workings of the car is not appropriate as a solution for the general public. In addition, nothing like this is even hinted at in the Owner's Manual or any user documentation. Maybe the solution is to not allow the traction battery to discharge below a certain point (higher than the current limit), and to drop into HV Charge if necessary. The marketing ramifications of this kind of change would be quite significant, as it would reduce both the EV range and the highway mileage, and thus affect buying decisions.

    The Boeing 737 analogy is a bit forced, but it's there. Maybe the Toyota stuck-accelerator is a better analogy, although a runaway engine is certainly more catastrophic than a dying one. But the bottom line is that Honda is playing with fire here. There's the potential that this could blow up and provide them with a bunch of negative publicity. I am glad that I am not on the team with the responsibility of setting the corporate direction on this one.
     
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  4. sniwallof

    sniwallof Active Member

    There are so many owners not having these problems, it still could just some tens of malfunctioning units (broken cars - lemons (possibly repairable)). [I just read some of the reports at carcomplaints, so likely at least in the tens]

    The Volts had some issues at the level of tens of failures. Some Gen 1 owners experienced loss of power brakes. There was some debate about whether they still had some manual brake remaining and just did not step heavy enough, but the failures were real. Then Gen 2, there were a number of complete loss of power events (I think only tens), several on the highway. I think most of those failures were traced to bad 12 V battery connections (possibly crimps or loose bolts or nuts, not at the battery). GM investigated all of them with some seriousness of purpose.

    Honda does not seem to communicate well with owners with concerns or problems. It is difficult to understand why. Maybe it is just the "compliance car" thing, and once made and sold to the required numbers, they want to wash their hands of the cars and the project, but it makes so little sense. Even if there are just two broken cars here (okay three, with Bob's agree bees), why on Earth would they not want to get to the bottom of the problem?

    Despite its foibles (not including the broken ones), it is such a wonderful and well engineered car. At least the design engineers must have taken some tremendous pride in the Clarity project. Even working perfectly, it can be a quirky car, but for many of us, that is part of the fun of interacting with it in so many different ways.
     
    Last edited: Mar 16, 2019
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  5. jackertracker

    jackertracker New Member

    I don't believe for a minute that this is the case. They put a lot of time, effort, and money into the Clarity models, and it's not just for compliance. The BEV, sure, and the FC because they wanted to push the envelope and promote that alternative energy source (those are limited to only a few states and CA, respectively). But the PHEV is the workhorse, selling in all 50 states, and they expect to sell 75K units in five years, IIRC. It's also kind of a halo project and Honda wants to promote energy efficiency long-term.
     
  6. Kevin McGuie

    Kevin McGuie New Member

    I love the car except for this issue. Since they sell them across the US, I dont think its a compliance car. This is part of their roadmap. We dont know how big the issue is. Those of us speaking up on this forum helps us determine that. We just need Honda to step up and deal with this. Im sure we've all been Honda customers in the past, which is why we were willing to take our chance on a version 1.0 product. Certainly, they dont want to lose their reputation. Unfortunately, so far, they arent taking this seriously. I think for some of us, without a fix, we arent getting our $$ worth since our families (wives, kids) wont get in the car. The way they are handling this (or not) is starting to leave a bad taste which will at a minimum turn off what have been loyal customers. The dealership service departments know less about the car than the customer. When the service foreman tells you the engine is just a generator to charge the battery, and nothing more, that speaks volumes for Honda training its technicians and service managers.

    MNSteve, you are right on.
     
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  8. insightman

    insightman Well-Known Member Subscriber

    limp-home mode
     
  9. Kevin McGuie

    Kevin McGuie New Member

    MNSteve, you said it perfectly. 100% right on. As for the Boeing comments, look at all the Captains here complaining that something wasnt right. It took the crash to get serious about it.

    https://www.theatlantic.com/notes/2019/03/heres-what-was-on-the-record-about-problems-with-the-737-max/584791/
     
  10. bill_m

    bill_m Member

    You may be right. But if the problem is, say, in the control units, it may be subject to organizational pathologies. Maybe the team that did the development have moved on to help out on the next hybrid or phev platform, leaving a less trained maintenance team to handle he difficulties. Or perhaps Honda had farmed out the work to independent contractors, who have also moved on. Lots can go wrong in software handoffs... (These are only blue sky speculations. Sorry for these worst case scenarios!)
     
  11. sniwallof

    sniwallof Active Member

    I noticed in one of the earlier fault videos, pulling over after an unexpected ICE start, stopping the car, and then restarting to get back to EV mode. I'm referring to the complaint that ICE comes on at the beginning of every drive in EV after some tens of seconds of driving. Maybe that Clarity "needs" to run its ICE for a bit for a prescribed run, and it is actively being prevented from doing so.

    See one of the other current threads, post #10 on ICE startups: https://insideevsforum.com/community/index.php?threads/car-switched-out-of-ev-mode-even-with-full-battery-charge.5079/#post-54260

    I wonder if where the engine is not allowed its normal warm up time (after each ICE start) on a regular or repeated basis by the driver, if there could be an instance where one or more possibly adaptive algorithms get into a "confused" state (yes, it should not be possible), causing a user induced failure condition. Not sure if the 12 V reboot can help here, or if it would take a dealer factory re-program to get back to the fully initialized state.

    Probably no relation to the limp-home mode power loss (unless that too is some kind of adaptive algorithm failure). It's equally likely that some of these failures could be the odd (almost random) bad electrical (e.g. somewhere on the 12V power bus) or electronics connection, say a bad crimp on one or more pins to some electronics module, which might be difficult to diagnose and correct by all but the most experienced techs.

    Or, there could still be a software glitch, although if it is software alone, it is odd that more of us do not see the same problems. OTOH, if it takes one or two additional failures (e.g. after some sensor fails, actual sensor fail, or bad wiring), then the 737 MAX 8 analogy may start to come into play. It usually take three three things going wrong to crash an airplane, often one of those is failure to take an appropriate action by the pilot in face of the failure/emergency (e.g. turning off the offending system, sometimes by one pilot pulling a specific breaker, while the other pilot is performing/flying that function manually).
     
    Last edited: Mar 18, 2019
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  13. bill_m

    bill_m Member

    I don’t know the complexity of automotive control structures, but if this is related to interrupt service routines where events may occur asynchronously, the problems may be subtle.
     
  14. Kevin McGuie

    Kevin McGuie New Member

    So, I tried this coming home tonight. Never have done this before since I try to get to and from work on EV only. I've had 3 trip meters with over 3000 miles between putting gas in, and at that, i've never put more than 4 gallons in. just turned 14000 miles, and today is the cars 1 year anniversary, but I digress.

    So tonights ride home, with 25 EV miles showing available, I hit my two mile hill climb and engaged HV/Charge per your suggestion. I got up the hill just fine and showed 21 EV miles. After a mile on level freeway, and HV/Charge still selected, I was doing 67mph steady (not accelerating), and wham the engine revved like the angry bees for no reason. Plenty of EV battery to be using Gas and EV. No reason for the ICE to be revving the way it was, acting like it was stuck in first gear (i know it doesnt have one, but best way to describe the condition) Turned off HV/Charge mode and put it back to ECON, coasted until EV mode came on, then accelerated back to the speed limit. I could tell the ICE was still on, but the icons did not show any power coming from it and the bees were gone. I could here it and feel it running. It never shut off the rest of the way home. EV showed the rest of the trip, and acted like it was in EV mode, with fairly quick acceleration, but the ICE RPM rose as I accelerated. No OBD to prove it. Just being familiar with the feel of the car.

    I completely understood the mountain mode approach (however agree with MNSteve that planning should not be required, and should be automatic via the onboard computer(s)), but this had plenty of EV range remaining. I was on level freeway when the bees came, and I was more or less in a coast/maintain speed mode, not trying to accelerate, just maintain speed. Its like something popped out of gear and revved the ICE. Temp outside was about 60 degrees. no accessories running like heater or ac. just the radio.

    Tried to video, but the glare on the displays interfered with getting good quality. Also, didnt turn down the radio soon enough. Not something I would consider publishable. Probably doesnt matter. The Honda factory guy thats suppose to "inspect" the car on Thursday will not do so with me present or look at any recordings I have. But this was an easy test, and one that I wont have to go out of my way to try again after I get it back from its inspection.

    I'll report again next Monday. And next time be prepared a little better for recording.
     
    Last edited: Mar 19, 2019
  15. Gearhead

    Gearhead Member

    The car won't dip into the battery reserve indefinitely. At some point it decides it had better put charge back in the battery to replace what was drawn earlier. In your test put back the 4 EV miles consumed climbing the hill . Seems like what I'd expect.
     
  16. MPower

    MPower Well-Known Member

    That certainly sounds like what happened when I tried driving up a really steep hill (truck escape ramp steep) at the over the 50 mph speed limit, accelerating from a left hand turn. I was in ECON with heater on and the car sipped up the hill with no hesitation smooth as could be in EV.

    But when I got to the top, totally on the flat and was STOPPED at a red light, suddenly the ICE came on quite loud. I don't think I would call it angry bees, but with no road noise because stopped, it seemed quite loud and startling because unexpected. The battery gauge showed that it was still more than half charged.

    It was as though a runner had just completed a race and then started to pant. I turned HV on and then off and it stopped panting. (I did not need any extra charge to get me home since it was going to be mainly flat or downhill.)

    I think it was shocked. I never had the accelerator pressed so far down. It wasn't passed the click, but may it worried that I was going to keep driving with a lead foot and it needed to prepare with as much charge as it could muster.
     
  17. Kevin McGuie

    Kevin McGuie New Member

    I'm not sure I follow. are you referring to while HV/Charge was enabled? or that the ICE never shutoff? I had high revs a mile after i got to the top of this hill. drove a mile with HV/Charge still enabled, while trying to get the phone out to video the high revs. There is no reason that the ICE should be revving so high, even with HV/Charge enabled. Most of the time, if its enabled, the engine noise/revs are not excessive while its charging. Its like driving in hybrid mode.

    If you are referring to the mention that the ICE never shutdown the remainder of the way home, HV/Charge was not enabled. If its not enabled, the ICE isnt replenishing the battery, nor did the engine icon display that it was running or charging.

    I'm grateful for your explanations, but I dont think we're on the same page. HV/Charge enabled on flat freeway should not equal high revs under any circumstances while there is plenty of EV range/KW left in the battery - Unless you are pushing the pedal past the detent and trying to go 100mph. Its never done that before on the few times I've used HV/Charge mode. I understood the battery being depleted to near 0 and trying to push a 4000 pound car up a hill with no EV assist, but not with a 50% charge, and a flat level drive.

    I showed the crappy video to the service manager so he could explain it to the Honda field rep (since I'm not allowed to). He agreed it wasnt right. The engine is over revving for no good reason.
     
  18. fotomoto

    fotomoto Active Member

    No, I did NOT say to use HV/CHARGE will ascending the grade. I said to build up some EV miles first; meaning BEFORE the grade as an energy buffer. Sorry you were confused. Then, tackle the grade with EV or HV modes with a sufficient EV buffer for the test.

    HV/Charge should only be used at higher speeds on (mostly) level ground. From an efficiency (nerd) standpoint, it shouldn't be used in most instances as plugging in is WAY more efficient and clean. I'm impressed that you made it up the grade just fine in this mode. Very interesting.

    What many are calling "angry bees" is the combination effect of the drone of the atkinson cycle ICE + non-shifting CVT that keeps the ICE at a near constant RPM + Honda's tuning attempts at NVH (noise, vibration, harshness). A common issue with new hybrid owners. My prius is really bad, my Cmax not so much.

    FWIW
     
  19. 4sallypat

    4sallypat Active Member

    Correct - the HV charge is to be used in high speed flat level type driving to recharge the battery using the ICE.
    If I am going to go up a hill, I will make sure I have some EV charge left, then switch to Sport mode and let both the battery and ICE get me the torque I need to get up the hill.
    Then only if the battery level is getting very low will I switch on the HV/Charge mode which is the least efficient mode.
    For long distance driving, I use the HV mode to get both battery and ICE running separate/together as needed....
     
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  20. Gearhead

    Gearhead Member

    I'll just mention that I've only used HV Charge mode a few times but in each case the engine immediately went to circa 4000 RPM which is what I'd expect. The one time I was going uphill at surface street speeds there was very little climbing power. I'm surprised Honda allows HV Charge at any time except when the car is idling. Even on level highway emergency power would be in very short supply.

    Has anyone used HV Charge when the engine wasn't pegged at max output RPM?
     
  21. MNSteve

    MNSteve Well-Known Member

    I don't use it often, and when I do it's during highway driving. Other than the car's indicator showing less mpg, I see no difference in engine operation. I expect there's a small increase in engine rpm but not enough for me to observe.
     
  22. Clarity_Newbie

    Clarity_Newbie Active Member

    Gearhead

    I actually took the time to place the Clarity I drive into HV charge mode while I was driving on a low SoC one day in March. (SoC ~ 20%) The Clarity operated in HV charge mode at 45 mph...increased to 55 mph...decreased back to 45 mph for about 10 miles round trip. The round trip includes turning around and starting from 0 mph to gain speed while in HV charge mode. Flat to gently rolling, 4-lane state highways. This loop was one of the few I did on purpose just to collect the data.

    The data for that test showed ~600RPM increase from what I normally experience. For example...the 55 mph run RPMs reached ~2600 - 2800. Normally, the data collected runs in the ~2000 RPM range at that speed. No decrease in power observed.

    Much more data needed but those are my results. I will not run anymore tests in HV charge mode...this was a one-off out of curiosity. It was only the second time I had the Clarity in HV charge mode since ownership.

    Maybe other folks have additional data for HV charge mode. Would be interesting to see.

    Hope this helps.
     
    Last edited: Mar 22, 2019
  23. Seoulbrova

    Seoulbrova New Member

    Read through the entire thread. So if I have a 90 mile trip I should use half the EV and save the other half for the return trip? In my previous plug in I just drove until the ev mode was done and it switched to hybrid mode for the remainder of the trip. Assuming a really long road trip I should just start in hybrid mode and save EV for areas where I'm at an incline?
     

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