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Greetings. I bought my lovely white Clarity in Feb 2021. I'm about to embark on my first long(ish) drive from San Francisco Bay area to Southern Cal (about 400 miles). I've watched all the videos about the 3 modes. Clearly I won't be using ECON, and most people discuss travel in HV, but 1 click or 2? And when is it best to use Sport mode?
 

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ECON is a modifier to EV, HV, and HV Charge modes. It reduces the blower speed and A/C cooling as well as really slowing down acceleration. For Sport mode, use it on two lane roads - turn it on when you're going to pass to get decent acceleration during the pass. Turn if off when you're done accelerating. The other thing I've learned is on divided highways keep the ACC set to the shortest following distance to avoid sudden braking when someone pulls in front of you. Put it on the longest distance on two lane roads to help you see around the car in front of you.
 

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Regarding HV, the most popular method on trips seems to be:

- Start off the trip with a fully charged battery (obviously)

- Drive HV the whole trip, except when you are driving on surface streets and you prefer to drive in EV for those sections

- Any time you are starting out after stopping (gas stop, meal stop, rest area, etc) you have to remember to press the HV button before getting back onto the freeway otherwise you will be in EV mode and before you know it you will have used up all of your EV miles. It's very easy to forget, if that happens use HV Charge to build EV range back up as far as it will go (just over 50%). You also may need to use HV Charge on the way home if you use up all of your EV miles doing a lot of surface street driving in L.A. And even if you are diligent about using HV, your EV miles will still slowly decrease during the trip, whenever it drops below 50% use HV Charge to build it back up again.

- When going up steep grades, if the engine noise gets to be annoying, go ahead and switch to EV. It will burn up your EV miles pretty quickly but once you make it to the summit then you will regain a lot of it back during the downhill section.

- Some people try and charge at free chargers or at their hotel or wherever. My opinion is that when I am on vacation it's not worth spending any amount of time just to save the equivalent of a gallon of gas, which is about all a full charge will save you. After all we bought our PHEV's so that we don't have to charge on trips we can just quickly fill up with gas.
 

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Sport mode+4 left paddles=FTW. 24/7.

Yes, use HV or HV+ on the road (you will anyways after 40ish hwy miles if you don’t or forget to switch at start up). Use up a few EV miles getting to the highway and switch over then. If you forget and drain the battery (you’ll forget eventually), use HV+ to get some miles back in the battery as a reserve for high power situations (long hills @ hwy speeds). HV+ on level roads/even throttle results in the lowest generator RPM and best fuel economy.

SF-LA means plenty of places to stop and refuel but it should be noted that in edge cases one can drain the gas tank dry and still drive on the remainder of EV miles to a gas station. BTDT

Amazing vehicle. Have fun!
 

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I’ve found that EV works best around town everyday and below 45 mph and switching to HV when on higher speed roads 55 and above for few miles than back to EV around towns. HV only on long Interstate Highways and longer trips. HV + when batteries get below about 40 percent.
 

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Totally agree. Just drove yesterday about 300 miles. I too forgot to switch back to hv after getting gas - easy to do. Also, I’ve observed that my ev gauge will still read 2 bars when the meter states that the battery has 0 miles remaining. This is comforting knowing that aClarity owner is extremely unlikely to be stranded even after running out of gas. It‘s like the old version beetle with the emergency tank. Of course we tech-savy owners would never get that low - right?
BTW: when I refilled, it took 6.5 gallons - whoops🤔
 

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0 EV miles is around 10% SOC which is why it typically shows two bars at 0 EV miles because each bar represents 5% SOC. To be more precise it is generally in the range of 8-12% SOC. The reason for this is that at 0 EV miles the car essentially becomes a regular hybrid, so you can think of that last 10% as if it is was separate hybrid battery reserved for that purpose. Of course in reality it's all one battery, but that's how the system treats the last 10% of SOC and why it does not include it as part of EV miles.

In the same way 0 HV miles is not really empty, if I fill up at 0 HV miles it takes about 6.7 gallons. That means at 0 HV miles I have about 0.3 gallons left in the tank which is about fourteen miles.

I have been at 0-0 before, i.e. 0 EV miles and 0 HV miles, at which point I probably had around five miles of EV left on the battery and around twelve miles of HV for a total of about nineteen miles of driving before I would have been truly stranded. I was only a few blocks away from a gas station at the time and that's where I went, even though I'm sure I could have gone quite a bit farther I had no desire to prove out my estimates.
 

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I confess, that I have had a history of running on empty. One time I literally coasted into gas pump 30 seconds “after” the engine died. I don’t think I would go empty again but as I said, nice to know there is likeLy a few miLes Left on ev👍
 

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Above 45 in HV mode the clutch pack engages and the ICE is mechanical connected to the wheels at a single gear ratio of I think .80 This is great for 55-65mph roads. If you drive faster it would be like driving a 8 speed transmission in 6th gear at 70mph; You will get less gas mpg.

It might be possible to get overall better trip mpg. When driving 70mph or great to do what I call charge and glide. If below 70mph. HV mode is probably going to be optional. Above 70mph let the ICE work most efficiently under a load by letting it charge in HV charge mode.

Yes- the ice will burn more fuel while charging. However, it’s using the ice in the more efficient load at that rpm.

Once at the max allowed HV charge, I think that’s 53%. You can switch the hv charge off by going back to EV. Now at 70mph the ice isn’t spinning, it’s off. For the next 20 (guessing) miles you can drive without any gas.

The new Toyota hybrid dual motor design uses a planetary gear set along with one of the electric motors to maintain the ICE operating in the peak efficiency load/rpm.

We don’t have that option in the clarity. We can only control our vehicle speed; knowing the clutch engages at 45mph. I would assume the peak gas mpg would be 50-55mph.

Above 70mph we can control some of the load on the ICE by making it charge.
 

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Disregard my above post.
The ice will not always connect to the wheels above 45mph. It can engage and disengage as the program picks.
 

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Disregard my above post.

The ice will not always connect to the wheels above 45mph. It can engage and disengage as the program picks.
True we can't control when it goes into "gear mode", but when in the speed range that you mentioned it seems to stay connected most of the time as long as the speed is steady. However when there are momentary accelerations or decelerations it disconnects, then connects again. This happens for example when following someone who is not driving at a steady speed.

We don't really know how much more efficient gear mode is than generator mode. Clearly there are some losses when generating electricity, we just don't know how much. But presumably gear mode must be at least somewhat more efficient than generator mode otherwise they wouldn't have taken the trouble to build in that capability.

Above approximately 65 mph there are two drawbacks, one is that gear mode is unavailable, so there would be whatever losses there are in generator mode. Also wind resistance will have a detrimental factor since drag is exponential, all cars suffer a hit in mpg when exceeding 55 mph, and it gets worse above 70. Good coefficient of drag helps but can only do so much.

Using Charge Mode above 70 mph might have added efficiency because of a more favorable position on the power curve, but we have no way to know that unless the car is put on a dynamometer. Whatever efficiency might be gained also has to offset the losses of sending electricity to and from the battery. Anecdotal evidence that I have read seems to indicate it's pretty much a wash. HV Charge in my opinion is all about providing a more pleasant overall driving experience. The gas engine doesn't bother me at all when I am driving at freeway speeds, because you barely hear it above the road and wind noise. But on surface streets I very much prefer driving in EV mode, so if I know that I am going to run out of EV miles, while on the freeway I run HV Charge to build up the EV miles that I will need when I get off the freeway (well maybe not need, but want). On longer trips HV Charge helps build up EV miles that can come in handy prior to climbing a long grade.
 

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“Above approximately 65 mph there are two drawbacks, one is that gear mode is unavailable”

Interesting.
I wonder why it won’t stay in gear lock up above 65mph?
 

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“Above approximately 65 mph there are two drawbacks, one is that gear mode is unavailable”

Interesting.
I wonder why it won’t stay in gear lock up above 65mph?
Gear mode uses a single fixed overdrive gear, which presumably only engages when it is more efficient to use it. Of course in a regular car there is no upper speed limit for the overdrive gear, even if efficiency declines at higher speeds it will stay in overdrive. But then again a regular car doesn't have any other options. Whereas in the Clarity it has the option to generate electricity to power the electric motor, so presumably above a certain speed generating electricity is more efficient than using the fixed overdrive gear. Just my guess anyway. While in gear mode it does sometimes also charge the battery, presumably that is when it has extra power beyond what is needed to drive the wheels.

Interestingly gear mode disengages when accelerating, even if only momentarily, my guess is that is for smoothness and responsiveness by giving the electric motor complete control of the power at that time. It also disengages when decelerating, maybe that's for electrical reasons because of regen, or maybe again it is just for smoothness. Apparently there is no problem engaging and disengaging the clutch on a constant basis, you wouldn't even know it's doing it if you aren't watching the display.
 

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Sorry....forgive the question. What is displayed when mode is active in 2021?? I dont recall seeing anything special on the dash in HV mode. Please kindly post picture, screenshot or page location in manual.

As a side question, if I plug in to charge is there a screen that shows charge status and length of time to complete?

Thank you
Mike (1 month new owner)
 

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Sorry....forgive the question. What is displayed when mode is active in 2021?? I dont recall seeing anything special on the dash in HV mode. Please kindly post picture, screenshot or page location in manual.

As a side question, if I plug in to charge is there a screen that shows charge status and length of time to complete?

Thank you
Mike (1 month new owner)
It can't be said enough...RTFM.
 

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As a side question, if I plug in to charge is there a screen that shows charge status and length of time to complete?
There isn't anything on the screen to even tell you if you are charging. The only indication is the green light on the charge door, which you cannot see while seated inside the car. You can use the HondaLink app but that is clunky to use in those situations as it takes time to update.

Sometimes I sit in my car for a bit while charging at the free Volta station that is near my Costco. Even though it's free it's not worth my time to just to sit there, but if I have emails to read etc. I will do that before driving off, enjoying free charging while running climate control. But if I am not sure it is charging, I have to literally get out of the car and look at the charge port to see if the green light is on. As mentioned I could use the app, but that takes too long. Oh and if you have climate running while charging, when you open the driver door that turns off climate, and whenever climate turns off, charging turns off at the same time. So if I forget that I have climate running and I open the driver door to check the green light, it's guaranteed that the green light will no longer be on because I just shut everything off by opening the driver door. So then while still standing outside of my car I use the fob to start charging, confirm by watching for the green light, then I get back in the car and turn on climate again with the fob.

Even better, there are times when I have been sitting in the car for over thirty minutes and climate times out. I use the fob to start climate again and go back to what I was doing, then later I do a face palm as I realize that I forget to start charging again. Well at least since I was plugged in my climate was running for free.
 

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Thanks 2002. Interesting lack of foresight by Honda on the charge status. Although I've read the manual some statements are a bit ambiguous and leave me scratching my head. Not the first time an auto manual missed a couple things that do not reflect reality. Thanks for the real world explanation. I agree this charging feedback is a bit unintuitive.

As for you EV, remember the lessons your Mom taught you about being rude. There are no stupid questions, just stupid mistakes. A forum like this welcomes any and all. So be nice. I found your history with EVs to be cool. This however is my first one and its a complex buggy. I appreciate folks taking the time to share. You've got nothing nice too say then simply click next.
 

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For a long distance I go to HV and let the computer do it’s job. Just before I reach my destination I go to EV to use up the remaining of EV miles, if any left.
 
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