MNSteve
Well-Known Member
But none of them work for Honda.... there are many technical writers better than me.
But none of them work for Honda.... there are many technical writers better than me.
Alex is my hero (along with @KentuckyKen ). Alex really understands how to make things understandable.Alex also explain
One clarification needed. Where is this gear icon of which you speak? I've looked for it both on the car and in the manual and cannot find it. thanksEngine drive mode is when the gear icon appears to indicate the i-MMD system has engaged the Engine-drive clutch so that the ICE is mechanically connected through gears to drive the front wheels. It turns out that this direct connection is the most efficient method of powering the car in some instances, such as when the load is light at expressway speeds.
Haven’t seen mine in a while, but I’m pretty sure it illuminates between the engine icon and battery gauge on the vehicle energy screen at the intersection of the energy flows to and from the engine, wheels and battery. You’ll only see it in HV when the engine is running with the engine icon is illuminated. Mine goes on and off on multiple times on the interstate. It has a narrow torque and specific rpm range so hills will cause it to declutch and you won’t see it below 50ish mph.One clarification needed. Where is this gear icon of which you speak? I've looked for it both on the car and in the manual and cannot find it. thanks
Ok I will put that screen up and watch for it. Unlike most of the people on this forum most of my driving is not in EV mode but in HV so I want to understand how that works better. 40 miles doesn't get me very far most days!Haven’t seen mine in a while, but I’m pretty sure it illuminates between the engine icon and battery gauge on the vehicle energy screen at the intersection of the energy flows to and from the engine, wheels and battery. You’ll only see it in HV when the engine is running with the engine icon is illuminated. Mine goes on and off on multiple times on the interstate. It has a narrow torque and specific rpm range so hills will cause it to declutch and you won’t see it below 50ish mph.
I use the hv engine mode on the highway because thats what the salesman said to do.
I find this part of your quote interesting. My experience with salesmen is that they will say a lot of things to sell a car, not all of which are correct. Case in point, my wife drives an Acura which recommends 91 octane fuel. She routinely puts 89 octane fuel in it "because the salesman said it was okay". Someone once told me the moon was made of green cheese, too, but that doesn't make it so.
As to using HV mode on the highway, I know that many on this forum advocate doing what the salesman told you, but I disagree. To summarize, most say to use electric mode to get to highway driving, HV mode on the highway at highway speeds, and save some battery charge for driving on city streets at the destination. I find this technique to be exactly the opposite of what I want to do.
Here is my thinking: The Clarity is rated at 44 miles per gallon city driving and 40 miles per gallon highway. For me, gas is now about $2.20 per gallon and my electricity cost is $0.139 per kilowatt. Since a "full" charge is approximately 15 kilowatts, the rated electric range of 47 miles costs me $2.085 or $0.044 per mile (15kW x $0.139 = $2.085 / 47 miles = $0.04436). At $2.20 per gallon, city driving costs me $0.050 per mile ($2.20 / 44 = $0.05) and highway driving costs me $0.055 per mile ($2.20 / 40 = $0.055). On a purely cost basis, HV mode is the least cost efficient mode for driving.
I realize there are a number of other factors that might come into play when computing cost, but I feel that these numbers accurately reflect the relationship between the cost of driving in the various modes. EV mode is the lowest cost, HV mode in city driving is higher. HV mode on the highway is the highest cost of all the modes for a Clarity.
So this begs the question; "Why force the car into HV mode, its most costly mode, when driving on the highway if you have battery charge left?"
For me, I never select HV mode. I drive all of my driving in EV mode until the battery depletes down to a level where the car decides to switch to HV mode on it's own. If I am driving further than the battery charge will get me, I want to arrive at my next charging location, usually home, with a fully depleted battery, maximizing those miles that I can at the lowest cost per mile.
Actually, the salesman is correct in this case. The manufacturer recommends 91 which does not mean it requires 91. You can use 87 or 89 if your manual says so. If the manual requires 91, you have to use 91. So you have to pay attention to what Acura recommends or requires.I find this part of your quote interesting. My experience with salesmen is that they will say a lot of things to sell a car, not all of which are correct. Case in point, my wife drives an Acura which recommends 91 octane fuel. She routinely puts 89 octane fuel in it "because the salesman said it was okay". Someone once told me the moon was made of green cheese, too, but that doesn't make it so.![]()
So I found the gear icon today but also found why I hadn't noticed it before. 90% of my highway driving lately is on Connecticut Route 9, and it is all up and down hills to the point that maybe 1 mile out of 30 showed the gear icon. When you're going uphill engaging the gear doesn't give enough power/revs to get you up the hill so it all goes thru the generator, and downhill the engine goes off. I also today drove Interstate 95 and that is flat enough that the gear icon was on more than half the time.@KentuckyKen is right. I tried to blow up the illustration from page 14 in the Owners Manual. The illustration is so small that it just got fuzzier. So I drew a red circle around the icon so you can at least know where to look on the Energy Flow screen.
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You've hit on one of the more perplexing aspects of the Clarity PHEV. Only when the clutch is engaged (Engine Drive mode) is Honda's claim of 212 hp available (see Engine Drive mode illustration below--see illustration of all modes here). If that's so, why does the car have to switch to the 181-hp EV Drive mode when you need max power? The answer has to be the gas-saving tall gearing used for Engine Drive mode.When you're going uphill engaging the gear doesn't give enough power/revs to get you up the hill so it all goes thru the generator
Thirty years ago I made my living as a technical writer, but there are many technical writers better than me.
I always try to avoid arguments on forums, but I disagree--I'm not the only one. There are many very technical people on this forum--especially those with knowledge about battery chemistry and performance--who have taught me many things about this great car.Perhaps there are, but you're the only one taking the time and trouble to explain things here.
Thank you very much for your valuable contributions to this forum! It's much appreciated.
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I always try to avoid arguments on forums, but I disagree--I'm not the only one. There are many very technical people on this forum--especially those with knowledge about battery chemistry and performance--who have taught me many things about this great car.
That's my guess too. With the tall gearing the engine is likely way below its hp peak at normal highway speeds. I would offer to try cruising route 9 at 100 mph and see if it stays in engine drive mode more, my guess is it would, but that road is always crawling with policeYou've hit on one of the more perplexing aspects of the Clarity PHEV. Only when the clutch is engaged (Engine Drive mode) is Honda's claim of 212 hp available (see Engine Drive mode illustration below--see illustration of all modes here). If that's so, why does the car have to switch to the 181-hp EV Drive mode when you need max power? The answer has to be the gas-saving tall gearing used for Engine Drive mode.
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