Or, “Which mode do I use?”
In September 2011 we wrote an article about the ECO drive mode on the LEAF. It has proven to be one of our most read articles. For the 2013 model year, Nissan has offered some changes to the system on the SV and SL trim levels. This article is an update of our previous article as the new B-mode did not exist on the 2011 or 2012 models. If you are unfamiliar with the basics of the ECO drive mode, we suggest that you start with our earlier article (found here), as this newer technology builds upon the previously existing technology. The 2013 S trim level does not offer the B-mode and will operate as before. We will dive a little deeper into the brake regeneration this time also. Near the end of this article, we will provide some casual test data to show the difference in operation among the various modes.
The Nissan LEAF now offers four distinct drive modes on its upper two trim levels – Drive, Drive ECO, B-mode, and B-mode with ECO (or as my wife calls it – Bahonkin’ ECO. Not really sure how she would spell it though). Let’s start with Drive mode.
Drive mode is engaged by moving the shift lever to the left and back one time. This is the equivalent of selecting Drive on a traditional automatic transmission on an internal combustion engine (ICE) vehicle. When in Drive position the accelerator pedal provides Nissan’s standard throttle responsiveness for acceleration. Lifting off of the throttle at speed provides mild regenerative braking. When you are accelerating, the electric motor turns the wheels. When you are decelerating the wheels turn the electric motor, which is now acting as a generator. Traditional friction brakes, be they disc or drum, turn kinetic energy into heat by creating friction. This heat is then dissipated into the air as wasted energy. An electric vehicles’ regenerative braking system captures some of that kinetic energy through the electric motor and sends it back into the battery as electricity.
The Drive ECO mode is engaged by placing the shift lever into the Drive position, and pressing the ECO button on the steering wheel. The dash indicator will now show D with ECO next to it. Pressing the ECO button does three things – first, it changes the responsiveness of the accelerator pedal by requiring the driver to press harder to achieve the same rate of acceleration; second, it provides slightly more brake regeneration than the Drive position; third, it slightly impacts the operation of the heater and air conditioner to improve energy usage. By doing all three of these things, range may be improved between five and ten percent according to Nissan.
B-mode is engaged by moving the shift lever to the left and back two times. The first movement will display D on the dash. The second movement will display B on the dash. B-mode provides more aggressive brake regeneration than either Drive or ECO. In Nissan’s words from the 2013 LEAF Owner’s Manual:
B-mode: Engages the regenerative braking system more aggressively on downhill slopes, and helps reduce brake use.
That seems to be a succinct and accurate description of B-mode. We would add that it is not limited to working only on downhill slopes. It also provides more aggressive braking in any driving condition.
Finally, B-mode and ECO may be engaged concurrently. Initially we thought that this would provide even more brake regeneration than B-mode alone, while also providing more resistance and slower responsiveness to the accelerator pedal. It turns out that brake regeneration is not enhanced over B-mode alone, but it does slow the responsiveness of the accelerator pedal, as it does in Drive.
Now for the non-scientific testing to validate the above statements.
We live near a parkway with a 55 mph speed limit and a short 50 foot elevation change over two tenths of a mile. We accelerated to 55 mph and coasted through the downhill portion of this elevation change. We did this three times for each of the four drive modes and averaged the results. This is what we found:
| Mode | Speed Reduction | Blue Regen Dots |
| Drive | 10 mph | 2 |
| ECO | 18 mph | 3 |
| B-mode | 35 mph | 4 |
| B-mode with ECO | 35 mph | 4 |
So the real question now is how does this help you in your everyday driving? Our intent is that it will better help you select the proper mode at the proper time.
If your everyday driving consists of significant stop and go city traffic (or stop and go freeway traffic for that matter) you can maximize brake life and further reduce maintenance costs with ample use of B-mode. We have learned that B-mode’s brake function is strong, and that our initial driving using this mode almost always included having to accelerate to the stop sign or traffic signal as we slowed down before we expected to. This reminded us of our racing days and this phrase in particular – the throttle is not an on/off switch. When approaching a stop sign, or red light while using B-mode, rather than lifting your foot completely off of the accelerator pedal, try just lifting part way off. Eventually you will learn the art of accelerating and braking just with the accelerator in many situations.
When driving in hilly terrain, the B-mode can be used quite effectively to modulate downhill speed. As its regen mode is relatively aggressive, you may find yourself shifting between ECO and B-mode depending upon speed and incline, perhaps even using Drive mode with slight inclines.
As far as the difference between using Drive and ECO, it may come down to personal preference. We know many individuals that have experience in German vehicles that prefer the pedal feel when in ECO, as many German makes offer firm pedal resistance. Others prefer the lighter and quicker responsiveness in Drive mode. One thing to keep in mind is that the ECO mode does provide a significant amount of brake regen compared with Drive mode, based on our findings. Also, a quick reminder that while in ECO mode maximum acceleration is still available by fully depressing the accelerator pedal.
There is no right or wrong way to use any of these modes. What you want to sort out for yourself is which mode do you prefer in any given situation. There is no way that you can damage the car by using any of these drive modes. If the B-mode offers too much braking for your taste, try the ECO mode. If the ECO mode isn’t slowing you down as much as you would like, try the B-mode. In the end it comes down to being able to personalize your car for your driving style. With all of these modes to choose from, you can tailor your LEAF to the way you drive making for a more enjoyable ownership experience.
Pingback: What does the ECO drive mode really mean on the Nissan LEAF? — Living LEAF
Nice description, I have a 2011 Leaf so the B option is not available to me but I’m curious if the rear brake lights are illuminated on the 2013 model when aggressive regen is applied. If not, maybe Nissan decided the effect is no more than a conventional car with engine braking and doesn’t pose a safety issue?
Gary – Welcome to Living LEAF. Nissan does not illuminate the brake light when using the Brake mode. When in B mode, the effect is similar to the engine braking of a 6-speed manual-transmission vehicle in perhaps fourth gear. It is not such an abrupt change in speed as to pose a danger to anyone following.
Does switching between modes while driving cause any issues?
Should I wait until I stop to change modes?
I like using D mode on the freeway and ECO on city streets.
Bruce – Welcome to Living LEAF. Sorry I missed your comment until now, but here’s your answer. You can shift between modes at any time and at any speed. I often use the B-mode on my 2013 LEAF when slowing down for a stop light, and then place it back into D prior to take off. Shifting into any mode will not damage anything while in motion. Nissan does a great job of preventing drivers from damaging their vehicles by doing things that would harm the vehicle or the driver. I hope that helps.
I’ve recently bought a 2017 Leaf and have noticed that if you shift into B mode while at speed, it doesn’t affect the braking until after you go below a certain speed, (20 or 30 KMs I think) or maybe until you come to a stop. Still playing around to figure out which.
Also of note, but not mentioned (and very effective) if you are in Eco B and set the cruise on a downhill, the Leaf will use maximum regen to hold you at that speed rather than just coasting and allowing speed to build up.
Never mind… I now think this is because my battery is full going down that first hill in the morning… my bad!
Chris – Welcome to Living LEAF. You’re right – there is no regen with a full battery. This is the case with all electric cars, as there is nowhere to send the generated electric power. The new 2018 LEAF has accounted for this by using the mechanical braking system when B mode is engaged, and the battery has a full charge, so that the driver experiences the same vehicle behavior whether the battery is fully charged or not.
I highlighted one of my friend’s Leaf experience in Coastal Virginia on my blog. He just reported that he’s now up to 4.2 miles per kWh using ECO + B mode.
We have had a leased 2013 LEAF for 20 months, and get 5.0 to 5.2 miles per kWh according to the car dash.
We leave it in ECO all the time, and avoid the freeway. Speeds of 35 to 50 mph.
One brave day I charge it to 100% battery, and drove 60 miles up and down mountains to a distant town with a Nissan dealer where I charged up and returned home. By avoiding the freeway and keeping it under 50mph, I used 67% battery each way.
Vermont
Robert – Welcome to Living LEAF. Thanks for your comment. As you have proved, the LEAF can be driven greater distances with juice to spare – even in mountainous terrain – if driven moderately. Not everyone will have the time or inclination to drive as carefully as you did on this trip though. Your experience does show the possibility of getting around 90 miles, if needed, from a single charge. I’m glad you’re enjoying your LEAF.
With 36,000 miles on the battery, I drove over 95 miles in the Rockies with over 3,000 feet of ascent to the pass summit, and back down the other side. Still had about 10-15% left in the tank on arrival. I was going slowly on the uphill portions – as low as 30 mph in steep sections.
Raf – Welcome to Living LEAF, and thank you for your contribution to this discussion. It will be helpful to many others.
Is there a difference in the amount of regen braking in B mode versus using the brake pedal to get the 4 green balls?
dat – Welcome to Living LEAF. When you see the power meter moving to the right (using power) or moving to the left (regenerating) you are seeing the total amount of power being used or regenerated. You will need to be on a pretty steep incline to see the power meter move all the way to the left without braking, or slowing from very high speed. When using the brakes and actively engaging the brake pad with the rotor, that energy is lost to heat. B (or Brake) mode will lengthen the life of your brake pads as they will be needed less frequently. Finally, when the power meter is all the way to the left, it doesn’t matter how it got there. You will always maximize regen without engaging the brakes. Hope that helps.
I have a 2012 SL. The B mode sounds like a good idea. I would probably use it. I live on Maui, on the slope of the volcano, so I drive down the hill, shop, and then drive back up. I never use anything other than ECO. I wish I could program my Leaf to default to ECO instead of having to move the lever twice. Then moving it twice could kick me back to D.
Stan – Welcome to Living LEAF. I’ve not heard your request from anyone else, but I can see that it might make sense for certain situations, such as yours. You might put your request on the Nissan LEAF Facebook page. Nissan monitors all comments.
2015 SL – The ECO toggle button, is on the right lower side of the steering wheel. The D and B modes are toggled from the shift lever. You do have to move the shift lever twice to go into D, then B modes. If you have the ECO on, it will be on the next time you drive the vehicle till you toggle it off. If you begin your trip on the mountain fully charged, you won’t generate that much energy, since you can’t charge more than 100%. Driving back up the mountain, will use up more energy. ECO softens the acceleration; B increases the regenerative braking. They are two different modes.
John – Welcome to Living LEAF. And thank you for your comments. I’m sure many will find them helpful.
if to drive in eco mode (doesnt matter on d or b mode) acceleration is harder. Question is that if acceleration is harder on eco mode, does this drain more battery in acceleration process?
Ralf – Welcome to Living LEAF. In the LEAF (and some other Nissan vehicles) Nissan uses what they call an eco pedal. This is an electronic accelerator pedal that provides additional resistance when in eco mode. The idea is that it basically makes you more aware of your intent to accelerate by making it more difficult to do so. When you turn the eco mode off, there is less resistance. To answer your question – no, it does not drain the battery more during acceleration. Many European vehicle owners prefer the feel of the eco mode as the pedal response is similar to what they are used to. It is also important to note that if you apply full throttle, you will retain the ability to achieve 100 percent acceleration.
should i leav B mode on whole time?
ted – Welcome to Living LEAF. I suggest that you use B-mode or D-mode as needed, depending upon your driving style. For instance, on the freeway I will typically drive in D-mode as B-mode slows the vehicle too much when the accelerator is released. I will engage B-mode at the freeway exit in order to assist in slowing down for the off ramp, and gain in regeneration. I will then usually drive in B-mode around town which provides for less need of using the brakes. Experiment with your own driving style and see what works best for you. You may change from D-mode to B-mode as often as you like. You will not damage your LEAF. I hope that helps.
Hi- New owner of a 2016 Leaf and learning a lot from your articles, thank you! Have a 3 mi commute each way that starts 700 ft up and winds down the hill to sea level, then back up at the end of the day never exceeding 30 mph for more than a few seconds… sounds like B-mode ECO might be my best bet to save the brakepads. No highways here!
Katie, welcome to Living LEAF. Glad the articles have been helpful. Your LEAF should serve you well for many years!
Hi, do you know if I switch to neutral and back to drive when driving on a highway will damage the gearbox? I ask because there is a slight slope when I drive to work, and I think I can just neutral down it, and then engage D/B when I need to slow down. I would get greater economy doing this. It’s not dangerous because there is no signal and I stay at the same speed. But I am not sure if it is ok for the engine/gearbox. Please offer advice. Thank you.
Hi Kirisawa – Welcome to Living LEAF! You may select any drive mode, including neutral, at any time without damaging the electric motor or the gearbox.
What would be the advantage of coasting when the idea of an efficient regen drive train is to recap energy for free when on a trailing throttle or going down hill.
Even using neutral there is nothing to be gained from reduced friction as neutral does not mechanically disengage the motor from the wheels.
This tech is not like combustion engine drive trains where the engine can be isolated by this technique.
dgate – regarding regen, when regen is used you are only getting back about two-thirds of that energy that you’ve already used. You can see an example of this here:
https://www.youtube.com/watch?v=sguPOEnnKk8
Also, keep in mind that the transmission is just a one-speed reduction gear – it is either in gear or not. So when you put it in neutral you are not in gear, disengaging the electric motor from the drive wheels as they are no longer mechanically linked – which is why you get no regeneration when in neutral.
In Krisawa’s case, when on a long slight incline the use of regen might actually slow the vehicle down below his intended speed, requiring the application of power to maintain the same speed. By placing his LEAF in neutral, no power is used, and he can use regen to maintain his speed as needed.
Finally, regen is not always available. If you are fully charged and your first driving event is down a long grade you will get no benefit from regen, as it does not work then. You can’t add water to a bucket that’s already full. Your own driving conditions and situation are the best indications of when to use, and when not to use, the regen that is available to you. I hope that’s helpful.
My 2015 leaf s has break and Eco mode, but I have noticed it only works under 90% charge. Is that normal?
Larry – Welcome to Living LEAF.
I think you’re talking about the actual brake regeneration that you get with Brake and Eco modes. You have discovered what all EV owners have found out – when the traction battery is fully charged or almost fully charged, there is no or little brake regeneration. Here’s why.
Keep in mind what’s happening – as the car coasts or slows down, the wheels are turning the motor. When you are accelerating the motor is turning the wheels. The importance of this is that the motor turns into a generator and sends power back into the battery when coasting or slowing down. If the battery is fully charged, or close to it, there is nowhere to send the regenerated power so the computer tells the system to dial down the regen to zero or almost zero to prevent overcharging and damaging the traction battery.
I hope that helps. Have fun with your new LEAF!
This has been a helpful discussion as I haven’t purchased my used LEAF yet. I’m considering a ’12 or ’13. Can about the same regen be achieved on the ’12 by lightly depressing the brake pedal (not enough to engage the brake pads), as B mode on the ’13? I like the ’12s lower price and seemingly higher build quality, if it can be driven as economically as the ’13. Although I like the ’13s more advanced L2 charging system, since here in AZ recharging is billed by the minute.
Sandy – Welcome to Living LEAF. If your charge rate is billed by the minute, you definitely want to get a 2013 with the 6.6 kW charge rate. It’s standard on the SV and SL, but optional on the S. You’ll know that the S has the 6.6 kW charge rate if it has the DC quick charge port. If it doesn’t, it will charge at the slower rate. That will be a much more significant economic factor for you than the regen rate (of either year). I have not found there to be a difference in build quality among years, but I have not studied it closely. Your question about slightly depressing the brake pedal sounds like it’s way more work than it’s worth. You’re talking extremely minor incremental gains in regen, with likely additional pad wear as you will engage the pads more than you think. Good luck with your decision.
Can you use rapid charger in nissan leaf that only has 3.3 charge capacity.I am about to purchase a Tekna model
Joe – Welcome to Living LEAF. I’m writing from San Diego, but looking at the nissan.co.uk website, it seems that the 3.3 kW on-board charger is standard and the 6.6 kW unit with quick charge port is optional. So it looks like you will need to upgrade to the optional 6.6 kW charger to obtain quick charge capability. You will want to verify this with your local Nissan dealer.
It depends on what you mean by “rapid”. The Tekna has the 3.3kW Mode 3 type 1 charger onboard, but it can also be connected to public CHAdeMO rapid chargers. 6.6kW is quicker than 3.3, but it’s not really considered “rapid”. (4 hours to full vs 30 minutes for CHAdeMO).
Edit: this is for the 2015 model.
Ake – Welcome to Living LEAF. certainly 30 minutes is longer than it takes to fill up a gasoline powered car, but it is a choice to drive electric.
Living Leaf-Can “B” mode be programed into our 2012 sl/sv, at the dealer? I purchased a used 2012 Leaf as a gift, and trying to find answers to her questions. She and I built a 1992 pick-up ev conversion that we just donated to a museum.
William – Welcome to Living LEAF. The Brake Mode (B mode) is only on 2013 and later LEAFs. It is not something that can be programmed into earlier vehicles but you will still benefit by the increased regeneration in Eco mode.
Hi can anyone give me an idea of charging costs in your respective countries. It’s currently free here in Ireland to charge.
Brian – Welcome to Living LEAF. Rather than country being the prime factor, I believe individual entity has more to do with it. Here in the States, there are a broad range of pricing structures – from totally free access on the one end, to monthly charges to access charge networks at the other. When EVs first came out in 2011, most charging was free as an incentive. As time went on, various pricing plans developed. There are several charge networks available and most require an access card. We are still working toward a system where anyone can charge anywhere easily, but that is still a way off. Generally publicly available for-profit charge stations charge something more than the basic cost of electricity so the vast majority of EV drivers still charge at home the majority of the time.
Hi there
The test results in this article show no difference between B-mode and B-mode and ECO used together. I’ve just got my leaf and, so far, have been using it for short, slightly hilly, journeys to my kids nursery school. I have used a combination of B and ECO mode and am happy with the feel of it, but wondered if I would be as well just using B-mode on it’s own?
Marie – Welcome to Living LEAF. In my experience, using both together does not provide more brake regeneration than using B-mode alone. Some drivers prefer the feel of the accelerator with ECO on (more pedal movement for acceleration) others prefer ECO off (less pedal movement for acceleration).
On a side note, I just read a study that shows use of brake regeneration extends battery life.
Hope that helps.
Hello Ernie,
I have a 2011 leaf and made the mistake of letting them proceed with the P3227 software “update”. I now have virtually no noticeable regen at all. Any remedy?
ref. links:
http://www.mynissanleaf.com/viewtopic.php?t=18726#p403255 3rd post down
http://daveinolywa.blogspot.com/2013/11/oh-where-oh-where-has-my-regen-gone.html
Vincent – welcome to Living LEAF. Once an update is performed it cannot be rolled back.
I only get half the miles when i’m in B mode but inD mode I get normal miles . is something wrong with my B mode. I use ECO all the time
Hi norm – Welcome to Living LEAF. I see that you posted multiple comments asking the same question. I moderate comments to prevent spam littering the boards. Now that this comment has been approved, all of your future comments will post immediately. To answer your question, when using B mode you will get additional battery regeneration, your LEAF will slow more quickly on throttle lift-off, and your range should be the same or better than in D mode (or ECO mode). If this is not the case, you should take your LEAF into the dealership and test drive the car with them to demonstrate the issue.
On motorways I use B mode because you don’t want a drag drive going at 60 miles per hour. Echo mode for the towns and city and down bank a definite for B mode.
Carl – Welcome to Living LEAF, and thank you for your contribution.
I recently bought a 2014 Tekna.If I use B mode with Eco all the time,does it consume more energy rather than using D mode with Eco
Some people are telling that the B mode is like the 1st and 2nd gears and D mode is like 3rd and 4th in a normal car .So
When we drive in lower gears it uses more gas. Likewise they tell when we drive in B mode in a freeway it consumes more energy .is this right?
Ransika – Welcome to Living LEAF. The people that you are talking with are providing you with a vague analogy that only partially applies. But to be clear, you are not using more energy in B mode, you are using less.
The LEAF has a one speed transmission, so there are no lower gears and higher gears. There is only one gear. When you engage B (or Brake) mode, you are electronically slowing the car when you lift your foot from the throttle while simultaneously providing more regeneration to the traction battery. So, in fact, you are generating power when you remove your foot from the throttle. When accelerating it matters not whether you are in Drive, Eco, or B mode. I hope that helps.
I just got a 2016 Leaf and wonder why the default mode is not B. What is the disadvantage of leaving it in B mode all the time and is there a way to program the car to always go to B mode?
Tony – Welcome to Living LEAF. Good question. You will find that B mode provides more aggressive deceleration as well as more regen. While there is no disadvantage to leaving it in B mode all the time, some drivers prefer Drive or ECO mode when on the freeway and don’t want it to slow aggressively with every lift off the throttle. One can get used to what’s called one-pedal driving, but it takes more focus to properly manage that one pedal. Using B mode will not necessarily provide more driving range, if that is your aim. At best, regen will return about sixty to sixty-five percent of previously used energy. It works best in around town driving, reducing the use of brakes to stop at intersections, and it also works well in mountain driving where you can use regen to slow rather than the friction brakes. I typically will use Drive mode on the freeway and B mode around town. I don’t know of any way to set B mode as the default driving mode. Best of luck!
I will drive my nissan leaf by constantly changing from D mode to B mode and vice versa to slow the car down coming up to roundabouts, traffic lights and cornering. Will this constantly changing modes when driving damage any gearing or electrical components.
Francis – Welcome to Living LEAF. Sorry for the delayed response, I didn’t see your comment until today.
You are driving your LEAF exactly as the designers expected you to. LEAF is essentially a computer on wheels, so you are just telling different components to perform different tasks at different times. Your driving style will not damage the drivetrain or any elements of the controlling electronics.
I just got a used 2015 LEAF model S, one-owner, AZ car, with only 10,000 miles, for $11000.
I keep ECO on.
I never use B because it seems like it would be a hassle to “shift” from D to B to D to B …
I use cruise control constantly, ON and then OFF to coast (with ECO) to stop light.
I am in city traffic, rarely exceeding 45mph.
The display says 4.6 miles per kwh.
Could I improve the miles per kwh by using D, B, D, B,… instead?
Jerry
Jerry – Welcome to Living LEAF. Sorry for the delay in responding – the system is not currently notifying me of new comments. In any case, the answer is you don’t need to switch back and forth between D and B. Just leave it in B mode for more regenerative braking. You are right that it does not coast as far with B mode engaged. You just need to recalibrate your right foot-to-brain connection to take that into consideration. It works extremely well in the driving that you describe. Think of it this way – in D mode, when you lift your foot off the throttle, you are putting a small amount of “gas back in the tank” as you slow. In B mode, you are putting more “gas back in the tank”. This is displayed on the power meter as white dots moving to the right when you are using energy, and blue dots moving to the left when you are generating energy. You are also conserving your brake pads, as the slowing is coming from the electric motor reversing its direction and acting as a generator. You are not using the brakes to slow in B mode. Please check back in after trying this and report on any change in your miles per kwh. Thanks.
Could you please tell me if its bad to use a power a extension power cord to charge your leaf?
Fintan, welcome to Living LEAF. Sorry for the delayed response. It could be dangerous to use an extension cord with the LEAF charge station. The LEAF owner’s manual states not to use an extension cord.