I drive in eco mode most of the time. It’s flat where I live. Tonight, my car randomly decided to charge the battery almost to full in eco mode going 40-45. I tried to feather off the gas to make it run on battery only but it refused. On my way home (was away from car for an hour) car acted normal again and used battery with normal charge/ev mode cycling. Is this some calibration technique these systems use??
Battery charging to almost full
1 - 20 of 22 Posts
I've had that happen as well. Pressing the EV button comes back with "EV Mode Unavailable" with no reason why. Once battery capacity nearly maxes out, EV mode operation returns to normal. I suspected it is some type of calibration, as it occurred when the car was warm and the cabin heat was off. I would love a definite answer. It's an infrequent occurrence, so I'm not really bothered with it. Anyone?
Joined
·
4,489 Posts
My battery charges to full a few times during my drive to/from work. My drive to work is 'mostly' downhill (55-65+ mpg) so the return trip is 'relatively' uphill (35-45+ mpg)... but there are flat spots in between. I usually opt for ECON mode, but have tested Normal and Sport modes over the same route, for comparison.
I drive with the "Power Flow" screen up on the center console to see where energy is being pulled or stored, in comparison to the Power/Charge gauge on the Drivers Interface.
I don't think there is a calibration technique between the modes. The modes approach power management differently, but the algorithms for each mode 'know' when to allow EV to run (when engine load and/or CVT acceleration is light). There are forum members like @Magikhat that prefer to optimize modes for mpg, but I'd argue that an individual hybrid mode already does a good job at managing electric/gas for great mpg (e.g. hybrid mode knows the conditions required for EV, rather than causing message that EV can't run when EV mode button is pressed). In the end, driving technique and results will vary!
I drive with the "Power Flow" screen up on the center console to see where energy is being pulled or stored, in comparison to the Power/Charge gauge on the Drivers Interface.
- On downhill drive in, EV kicks in often/easily which is no surprise.
- On the return trip, EV kicks in when the engine load is light (generally in blue section of Power meter).
- While in the blue section (gas/electric use), the battery will charge if I'm driving with a low enough load on the engine.
- In all the modes, I end up with about the same battery level by end of drive (8+ bars on outbound, 5+ bars on return).
I don't think there is a calibration technique between the modes. The modes approach power management differently, but the algorithms for each mode 'know' when to allow EV to run (when engine load and/or CVT acceleration is light). There are forum members like @Magikhat that prefer to optimize modes for mpg, but I'd argue that an individual hybrid mode already does a good job at managing electric/gas for great mpg (e.g. hybrid mode knows the conditions required for EV, rather than causing message that EV can't run when EV mode button is pressed). In the end, driving technique and results will vary!
Joined
·
4,489 Posts
As an add, I just remembered seeing this thread on "EV Mode Unavailable" which might also be helpful reading/reference for current topic.
Unfortunately, that discussion never got the answer for the conditions Mobilcam and I are encountering. The conditions I had were perfect for EV mode, yet it never engaged no matter how much I coaxed it to do so. Once battery pegged, everything returns to how it should have been.
I have seen this happen to me in normal mode, too. So far it has occurred only once so I thought it was a glitch. Didn't know others have experienced this until now.
Joined
·
4,489 Posts
Honda seems tight-lipped about publishing even general info on their algorithms, and I haven't found anything Honda-specific beyond the condition checks mentioned in prior thread for "EV Mode Unavailable":
- The high voltage battery charge level is low.
- Vehicle speed is too high.
- Speed is above 25 mph while engine is in warm-up operation.
- You fully depress the accelerator pedal.
- You are driving on a hilly road.
I've chalked the EV management up to "the car knows what to do for it to switch..." (Which is another reason I personally choose not to fuss with changing modes during a drive.) When I've seen the battery charge up rather than switch to EV, I can usually associate it with one of these conditions - e.g. too much of an albeit minor hill; gas engine/coolant is cold; climate system running.
Some may dismiss the following since it's not Insight-specific, but I think there's helpful info to learn from diverse resources especially as the Gen3 Insight is so new and there are some common/comparable technologies. That being said...
- Toyota Hybrids list similar self-checks as for Honda (hybrid system, coolant temperature, battery charge, acceleration speed, pedal positioning) and similarly displays "EV Mode Unavailable" if any of these requirements are compromised. No mention of a calibration or reset is made.
- This Clarity thread on excessive ICE vs EV engagement mentions a older (2013) published paper from Honda engineers on overall system efficiency being their primary goal, rather than extensive EV operation. The Clarity doesn't have an EV button because the assumed default is electric mode; however even their owners notice situations where the ICE runs rather than EV. Opinion was split on whether continuously running the car (keeping engine warm) or turning the car off/on again (for EV reset?) yielded better result.
- This Clarity thread on "Engine vs EV" explores engine temperature requirement via OBD, and a 'length of time' trigger for which the gas engine must run.
Joined
·
158 Posts
I have not seen that happen yet. But then again my battery stays on the low side most of the time unless I go down a long hill, or use Sport Mode. 40% - 50% in Normal Mode is typical. Sometimes only 30% when I could use some more juice for a hill coming up. Then it depends on the ICE a lot.
I was actually wondering if there was a calibration procedure. But until I get into higher temperatures, I can't say it will always be that way with my Insight. Or maybe NY cars have a different charge algorithm because of the 10 year warranty???
Phil
Joined
·
299 Posts
That's been my approach starting out as well. Although I'm still trying to figure out what the system defines as "a hilly road." Many flat appearing roads tell me EV Mode Unavailable, yet EV turns on at bottom of steep hills while traveling 55 mph.
Once I figure out what the system "wants to do" I use the buttons to tell it "do it here" "do more now". This way the system is doing what its going to do anyway, but under real world conditions I think best for mpg, or other purposes.
Joined
·
4,489 Posts
I'm trying to figure it out too. It seems like it's related to 'perceived engine load' - possibly linked to CVT measure/monitoring? I drive with the "instant fuel economy" indicator on screen; it seems EV is most likely to kick in once engine load is light enough (i.e. instant fuel economy is at max and/or CVT has downshifted). Not entirely sure, but trying to monitor for related things that aren't listed as limiting conditions for EV.
Attachments
One thing I’ve noticed on my flat 50 mile drives to work is that if you’re at or above 75mph the ICE will stay engaged 90 percent of the time. As you drive, the system will charge the battery just shy of the top two marks. Once the battery hits this level, I believe the battery is reduced to a sustaining charge state as the instant mpg rises up to around 45mpg and stays there. Pretty neat that you can still get 45mpg from this little engine at those speeds.
Joined
·
299 Posts
I've noticed the same thing regarding "perceived engine load" (lovely phrase by the way!), but I watch the movement of the pointer on the power meter to determine the amount of load the system is perceiving. I also use the instant fuel economy screen. It seems that movement of the instant fuel economy slider from a low end toward maximum occurs just prior to EV green light coming on.
Joined
·
299 Posts
I have similar experience, both with ECON on and ECON off. I've been watching it, and it seems to be part of an extended warm up process.
I haven't got the full process figured out yet. But it seems that there may be at least two phases to full engine warm up. The initial phase raises the engine to a cool state from cold. This leads to relatively normal EV on / off operation. A second phase involves extended engine operation with battery charging to the 7-9 bars range. Perhaps the engine has moved from cool to cozy warm? After battery discharge there is a return normal EV on/off, but it seems more to be doing so in a faster, crisper, more effecient manner. .....just my speculations, love to see some tech. writing on this.
Joined
·
299 Posts
I took a little drive and am still stuck and wondering why on certain sections of road pushing the white EV button will not engage EV Mode. Even though the owners manual explanations for it not engaging do not apply.
The car automatically engages EV Mode. Runs in for awhile then disengages. Engine runs, charging up the battery, then EV re-engages. During a period with automatic engagement of EV Mode I may push the white button to "lock in" EV mode. This allows EV to remain engaged a little longer, digging deeper into the battery power reserve, before automatic dis-engagement. Also with EV locked in, EV remains engaged to a higher acceleration load point (the blue /gray line on the power meter).
During normal driving conditions (eg the bottom of a hill) and strong battery (4 bars+) I may push the white EV button. Most of the time EV Mode engages. If not I'll get a "battery too low" or "engine too cold" notification. ...Understandable.
The problem is "EV Mode Unavailable" and the owners manual explanations do not apply. This happens repeatedly on certain sections of roadway, under various temperatures, battery states of charge, engine warm up, engine acceleration load conditions (light, very light, and zero), and vehicles speeds (all under 45 mph). Why? What are the limiting conditions operating here?
A CVT / transmission downshifting situation is certainly a very reasonable possibility. So I went to the Honda Press Kit for some help and found the following, which leaves the question unanswered.
"....Unlike many competing hybrid systems, Honda's operates without the use of a conventional stepped or continuously variable transmission, utilizing instead a high-capacity lock-up clutch that connects the engine/generator motor combo to the propulsion motor. This allows power to be supplied directly from the engine to the front wheels, supplementing the propulsion motor under certain conditions for either maximum power or efficiency.
...
Drive Force Transfer
Like the latest Accord Hybrid, Insight is not equipped with a conventional stepped or continuously variable transmission. Instead, motive force transfer is accomplished through the interaction of Insight's gasoline engine and two electric motors. Coordinated by the ECU, this form of drive force transfer offers smooth and predictable acceleration matched with efficient low-rpm highway cruising when the gasoline engine is in operation. Gasoline engine shutdown is seamlessly integrated into the operation of the vehicle when appropriate.
The drive force transfer system operates without the need for a torque converter, mechanical pulley or belt. It instead uses two motors for driving and generating power. The system is optimally and rapidly able to control both engine and electric motor rotation in order to deliver higher fuel efficiency and quicker engine response in each driving mode.
When cruising at mid- or high-speeds in the high-efficiency range of the engine, a lock-up clutch is engaged, connecting the drive motor to the generator motor to transmit engine torque directly to the drive wheels as efficiently as possible (Engine Drive operation). In EV Drive operation, when the battery-powered drive motor is used for either acceleration or regenerative braking, a clutch disengages the stopped gasoline engine from the drivetrain to eliminate efficiency loss from mechanical friction in the engine."
The "EV Mode Unavailable" message gets me quite frequently. I've kind of gotten to accept it and now rarely try to force EV mode via the button. I figured Honda knows what it's doing. I generally stick to ECO mode and let the Insight do it's thing. I'll kick in EV via the button to get over the hill if I know I'll have a downhill to charge the system. Other than that, I let the Honda magic do its thing. I no longer use sport mode on hills but rather, try to keep things in the blue of the power meter. I leave plenty of time to get where I'm going, so I don't need to speed. My last three tanks have been above 60 mpg, and some individual drives have achieved high 60s to over 70mpg. I think I finally have things figured out. We're a few weeks away from summer gas, and outside temps are rising. It will be interesting to see what the summer numbers are. I've gotten mid-70s going to work. Dare I dream about 80?
Joined
·
299 Posts
I've been driving pretty much the same way.
EV Unavailable is relatively rare for me, EV kicks in most of the time that I push the button. Asking these questions is perhaps part of my seeking "more?" Who knows, perhaps an answer will help you get to 80 mpg on a drive to work? BTW What kind of speeds, traffic, and terrain are involved in your drive? My knowledge of New Jersey is limited to the NJ Turnpike (New Castle, Del. to GW Bridge) and 3 visits to Newark airport. I was able to find Princeton and eventually Phillipsburg, but they were just lines on a map.
I live in "farm country" of New Jersey. Not many out-of-staters ever get to see it. It's rolling hills with an average of 45mph. I am in the northwestern part of the state - as far removed from the turnpike as you can get.
Another thing I noticed. With working from home for the past two weeks I haven't had my daily 80 mile commute, so I haven't fueled up in a while. And in Eco mode, with less than 50 miles left in the tank, I noticed my battery is up nearer 7-8 bars as I'm driving. Wondering if the system is keeping the battery high so if the gas runs out, you can electric drive it to the gas station. Wondering if that's a real thing, or just circumstantial based on my limited driving for the past week. I fueled up today with 20 miles left, and it only took 8.5 gallons.
Interesting idea. I actually noticed the same but rather randomly during the week. Well, when I used to drive haha. I also drive in ECO all the time so my reasoning was that the ECU tries to keep the battery at a high charge every so often to keep the battery cells "alive" and healthy?I Kind of use it or lose it theory.
The battery will occasionally cycle to 80% as a matter of conditioning. I find it annoying when it happens right when I'm expecting a sweet, gravy spot of EV only to have the ICE not turn off.
In the case of charging to full, it's likely a matter of driving very short trips (< a mile or two) with a cold engine. The car never has the chance to utilize EV mode. Although our Insights are smart, mine has never maxed the battery because of low fuel - I've driven to/below zero miles of range several times with no change in how the battery behaves.
In the case of charging to full, it's likely a matter of driving very short trips (< a mile or two) with a cold engine. The car never has the chance to utilize EV mode. Although our Insights are smart, mine has never maxed the battery because of low fuel - I've driven to/below zero miles of range several times with no change in how the battery behaves.
1 - 20 of 22 Posts
Join the discussion
Join now to ask and comment!