Clarity Issues

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

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  1. petteyg359

    petteyg359 Well-Known Member

    Put it in HV from the start and leave it. It will use the battery when accelerating or when it needs power to climb a hill. Maybe if you know you can recharge while you're there, switch back to EV at <EV range leftover> miles to go. Or just leave it in HV the whole way. HV with a full battery gets ~50 MPG easily.
     
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  3. fotomoto

    fotomoto Active Member

    Wellllll, it depends. :) If you're mainly traveling level or rolling type hills, do what ever you'd like. If it's steep grades, same a good portion of the battery for climbing.

    My personal advice for EV/gas usage on long trips is to use EV primarily for speeds <45mph (city/urban) and gas for anything greater but to aim to arrive home (or your destination charger) with as close to zero EV miles as possible.
     
  4. Seoulbrova

    Seoulbrova New Member

    So HV mode with full EV gets better mpg than HV when EV is used up? It didn't seem to make a difference in the Prius plug in. I'm mostly all highway miles and flat terrain.

    Any long distance road trips then should primarily be on HV with a full EV then since I wouldn't be able to guarantee ability to charge in places I've never visited.
     
  5. petteyg359

    petteyg359 Well-Known Member

    Yes. The engine alone cannot drag the car up a mountain, or even up a shallow hill from a stop light. It needs battery power to do that. If the battery has plenty of charge, it doesn't need to keep the engine running while you're stopped at a light to keep the minimal charge in the battery. That alone is how basic hybrids like a Prius get such high MPG - turn off the engine when you don't need it running.
     
  6. MPower

    MPower Well-Known Member

    Folks have been complaining that the ACC does not accelerate up to speed quickly enough whennpassing a vehicle that has caused it to loose speed. I have experienced that, but today I was paying more attention and here is what I experienced. When i put the car in ACC on the inter state to do about 68 mph (which equals 67 on the speedometer) I noticed that the distance bars came on at less than the max so I clicked until I got the maximum distance (the interstate is not very crowded in Vermont).

    When I pulled out to pass a slower moving vehicle, the car accelerated back up to speed just fine with none of the hesitation that I and others have noticed. Has anyone else noticed this?
     
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  8. KentuckyKen

    KentuckyKen Well-Known Member

    The easiest way to get good acceleration with ACC is to either turn off ECON or use SPORT. Try it and you’ll like it.

    HV mode is much better for performance and lower engine noise if you have a good amount of charge. You don’t need it to be full though. I don’t know the exact minimum that’s needed to avoid the angry bees but nearly full to a little over over half has worked fine for my few out of town trips with some steep hills.

    One year plus and I’ve never heard the angry bees but I’ve only let the charge deplete once. That was on rolling hills with no passengers and 55-60 mph and it worked out fine. I wouldn’t want to try no charge on steep hills, loaded up, or at high speeds. Never used HV Charge and don’t plan to.

    8,500 miles on 15 gal of gas. The Clarity is hands down the best car I’ve ever owned. It’s ruined me though. I’ll never be able to buy a gasoline engine again. Not even for the yard. When the mower, blower, and weed wacker die, they’ll go electric too.
     
    Serge likes this.
  9. insightman

    insightman Well-Known Member Subscriber

    What, does your Clarity just stop in its tracks when you try to go up a mountain or up a hill from a stop light with no battery power available? Many people on this forum claim they can go up steep hills on ICE power alone without problems. They may, however, complain about the sound of the engine racing at 4500 rpm.
     
  10. MPower

    MPower Well-Known Member

    It's all hills and mountains here. The car seems to deal with them without angry bees. I am always driving in ECON. Have never gone past the detent because my legs are too short. I have never driven in SPORT. I drive like a little old lady for good reason (cause I am).

    Only had what I think were angry bees once (sounded like ordinary 2012 Prius Plugin behavior to me. That car could really roar on the very same interstate that the Clarity takes without a murmur.) That was when I had 3 people in the car with stuff and we were going uphill at over 70 mph in NH (They have 70 mph speed limits. VT does not have speed limits higher than 65). I am convinced that the Clarity does not approve of driving more than 70.

    It seems that a lot of folks complaining about the bees describe them happening at speeds over 70.

    I haven't tried the road with the 9% grade with 0 battery yet, but it will happily go up in EV ECON.
     
    Clarity_Newbie and insightman like this.
  11. petteyg359

    petteyg359 Well-Known Member

    ICE power alone means zero bars on the battery. If anybody has actually done that I'll be quite surprised. On the power display, I can watch even a slight incline cause it to shift from ICE+gear moving and charging the battery to drawing power from all three (ICE, battery, direct gearing) sources.
     
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  13. Garry2

    Garry2 New Member

    I had what seems like a unique issue with my clarity and an uphill section on the highway today. On my daily commute once I get to the highway with ~75% SoC I kick the car into hv mode as there is a steep hill 4 miles after the start this gives time for the engine to warm up and start providing power. However halfway up the hill I noticed a drop in power and my speed was dropped 10mph in a few seconds and continued to drop even pressing the accelerator past the click. I then noticed that I did not hear the engine revving. The car then started to gain power again 3/4 up the hill and I was able to accelerate again, but still no revving.
    I continued my commute and after 10 miles saw that my battery was below 40% SoC and the engine was still not revving or charging the battery. I tried switching driving modes and and going in and out of hv mode and hv charge mode, but the engine would not get past idle rpm. I would not have enough battery to get to work. Before the interstate I stopped and a red light and shut the car off and then back on. I switched to hv mode once I was going again and suddenly the engine started revving and charging the battery. I have 17k miles on my car and this is the first time it occurred.
     
  14. MPower

    MPower Well-Known Member

    This sounds like the loss of power that other members have experienced even with plenty of battery left. I think there is some condition that causes the car to get "confused" (technical term). When that happens on your computer, you swear and reboot while you go make a cup of tea. On the highway, that cure doesn't seem like it would work so well. Sounds like life with Windows 3.1 in the bad old days.
     
  15. ClarityBill

    ClarityBill Active Member

    Garry2;

    That seems like the mysterious 'drop in power'. You were fortunate to have some battery charge available, and it seems like you are very aware of what was happening. I am fascinated by this (dreading the time it happens to me), so there are a few questions:

    When you say ~75% SOC - How do you know that? OBDII? EV miles? What is plan of operation - do you fully charge every night, switch to HV at a special spot in road?

    What was the outside temperature? Was it any colder than your normal commute?

    How long after the initial switch to HV mode did this occur (miles and minutes)? Did the engine rev up before the hill, or would this have been the first time you expected it to rev up?

    Do you normally get into gear mode? Did it achieve gear mode before the hill?

    Do you normally lose EV miles while going up the hill in HV mode? If yes, how many?
     
  16. Seoulbrova

    Seoulbrova New Member

    The mysterious drop in power seems like a major safety concern not a minor annoyance. Is Honda working on some software patch or update or could we potentially see a full scale recall?
     
  17. Gearhead

    Gearhead Member

  18. ClarityBill

    ClarityBill Active Member

    Garry2:

    Another question: Did you notice if the 'power bar' on the dash went up, when you pressed the accelerator, but had no power?
     
  19. The Gadgeteer

    The Gadgeteer Active Member

    If the Clarity is designed properly the Clarity’s software “should” never put the car in a dangerously low power situation.
    Even if the driver makes poor mode selections the engine and battery “should” have enough reserves to handle any steep hill a driver will encounter in the market sold. Even if that means the software needs to temporarily switch modes, cut out high power consumers like heat, allow dipping in battery reserves, increasing engine use time, and increasing engine rpms. Loss of power is not acceptable.
     
    Mark W likes this.
  20. ClarityBill

    ClarityBill Active Member

    I would like to understand this loss of power situation, so I can recognize it quickly, and respond appropriately.

    On ICE cars, people would accept a loss of power if there was a piston rod sticking through the side of the engine, or an empty gas tank. Some failures on an ICE are obvious, and expected.

    Seems like Garry2's description could be a flaky accelerator pedal sensor... I wonder what kind of redundant systems Honda installed for that, and other critical pieces.

    I asked about the power meter, to see if there was any response to the accelerator. Years ago, failure of the accelerator pedal (and other sensors) was a discussion when designing drive-by-wire systems. Finding a flaky sensor is the toughest troubleshooting of a system.

    I wonder if ACC operation had power available? Has anyone experienced the loss of power during cruise control operation?
     
  21. insightman

    insightman Well-Known Member Subscriber

    Actually, at least one member of this forum has seen zero bars on his battery charge gauge--it came from his irresponsible dealer that way. I was reacting to your statement, "The engine alone cannot drag the car up a mountain, or even up a shallow hill from a stop light. It needs battery power to do that." I don't have any nearby mountains, but I believe that if the Clarity battery charge gauge is down to 2 bars (what I call 0 EV power), it will still go up a mountain and it will continue to display 2 bars on the battery charge gauge as it goes up that mountain. If the battery charge remains constant at 2 bars while driving up the mountain, then I maintain that it is the ICE that is dragging it up there, without help from the battery.
     
  22. Gearhead

    Gearhead Member

  23. Clarity_Newbie

    Clarity_Newbie Active Member

    Insightman

    What I have observed from the data collected differs from your theory..."then I maintain that it is the ICE that is dragging it up there, without help from the battery"...

    From data collected on 3 Clarity's...it appears the last 2 bars on the SoC gauge do indeed have a purpose. The link below are my thoughts posted in an earlier thread.

    The gist of it is...I lean towards thinking the last 2 bars represent "emergency electrons" which are rarely used and only used in situations where the on board computers sense a need to help propel the vehicle. As noted in previous threads...what has been constant in all three Clarity's when EV=0 and SoC at 2 bars/10% emergency electrons...the ICE throws as much energy back into the battery as possible to keep charge from dropping much below 10% while still using energy as needed to the drive train as evident by the energy flow screen.

    Link to initial data results and discussion
    https://insideevsforum.com/community/index.php?threads/soc-thoughts-relevant-to-excessive-high-revs-power-loss.4538/

    I understand much more data needs to be collected...or Honda just comes put and tells us straight-up what the deal is.

    At the end of the day...I'm not sure anyone truly understands what the last 2 bars represent or if/how that energy is used or designed to be used. I offer results of data collection...that's all...no concrete answers yet.

    Have you ever put a device on your Clarity to see how it performs in the field? RPM's relative to SoC and/or MPH? Try driving to EV=0 miles then watch/record the SoC while you continue driving.

    Nothing but good intentions for a friendly debate.
     

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