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Discussion Starter #1
On the test drive of new leaf, salesman commented that when in ePedal mode, lifting would make the brake light come on.

Surely it has to be a little more smart than that - stupid example, if I have my foot to the floor, then lift very slightly then I'm almost certainly still accelerating.

Reason for wanting to know, if balancing the pedal so as to coast, wouldn't want the brake lights to flicker on and off. Want the person behind to know when I'm braking, not letting a tiny bit of speed off.

Been wondering this but it's the kind of thing that's hard to know on the test drive unless you have a friend follow you around....

+1for a leaf40 forum please, admins
 

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Coasting won’t bring the brake light on, neither will lifting off lightly and only decelerating lightly, once you lift off properly the brake lights will come on.

That is how it works on the Model S and pretty sure there is a threshold at which point the brake lights must come on. E.g. 15% braking, IIRC it is a legally required function.
Edit:
http://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/R13hr2e.pdf

Detailed in there.
 

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I remember seeing a video on Youtube that stated that the brake lights are triggered at 0.2g of force which is a bit above the g force you get from ICE engine braking. Sounds good to me.
 

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I heard similar on the test drive when I asked, it's at a certain limit, though the salesman couldn't remember exactly what.

I'd be interested to know if it's based purely on the brake force being applied, or the actual deceleration of a car. For example going up a steep hill if I lift off the car will decelerate strongly even if i don't brake. So applying brake lights based on actual deceleration of the car would not mimic an ICE car.
 

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Vehicle decelerations
Signal generation
≤ 0.7 m/s2
The signal shall not be generated
> 0.7 m/s2 and ≤ 1.3 m/s2
The signal may be generated
> 1.3 m/s2
The signal shall be generated

From the doc, there is hard limit for signal or not and an area between to allow for coasting etc. it is not linked to Regan it is linked to the rate of change of the vehicle speed.
 

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judging by the long annoyed beep of the horn I had from the Audi behind me on my test drive when the motorway into Leeds goes from a 70 to 50 mph, I'm guessing that it doesnt come on until you are decelerating really quite harshly....
 

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Does the epedal braking vary according to charge, like B-mode on the current Leaf does?
For example, on the current Leaf, B-mode has next to no braking effect if the battery is fully charged.
 

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As I understand it E-Pedal will use the friction brakes when regeneration would be too strong for a fully charged battery.
This, I like.
It suggests more consistent 'engine braking' than the current one.
Next to zero engine braking when you're at 100% in snow is scary.
Although I suppose you could argue using the brakes is using the brakes, whether it's the car applying them or you....
 

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judging by the long annoyed beep of the horn I had from the Audi behind me on my test drive when the motorway into Leeds goes from a 70 to 50 mph, I'm guessing that it doesnt come on until you are decelerating really quite harshly....
Or they were just a douchbag following too close not paying attention, and got startled when they didn't have a bright red brake light to wake them from their slumber...:p

The lift off regenerative braking on my Ion is fairly modest at 70mph, not much more than engine braking on an ICE and I still get people coming up behind me too quickly when I lift off the throttle, due to the lack of applied brake lights. (I presume the car predates the regulations about brake light application with certain amounts of deceleration as it never applies the brake lights with throttle pedal only regen)

A couple of days ago on the motorway my dashcam caught a car in the far left lane (which was becoming an exit only lane) slow down and indicate to fit in a gap to the right to get out of the exit lane in plenty of time before it split off - the car slowed relatively quickly granted but it was nowhere near abrupt or emergency braking, only for a big furniture truck who was charging him down to swerve into the hard shoulder to avoid him and give a long angry toot at the car as it passed - when the truck was completely in the wrong for speeding and in no way maintaining a safe following distance! :mad:

I think there are just a lot of idiots out there that follow too close and have no conception of what a safe following distance is, brake lights or no brake lights. If you can't stop in time because the brake lights on the car in front of you didn't come on, you're still in the wrong for following too closely and not paying attention.
 

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If you can't stop in time because the brake lights on the car in front of you didn't come on, you're still in the wrong for following too closely and not paying attention.
A bit harsh, isn't it?
I dare say there's plenty of us on here would get caught out if someone with completely inoperative brake lights suddenly slammed the anchors on....
All very well going on about safe distances etc., but real life doesn't work like that.
Try leaving what the highway code probably considers a safe distance on a motorway and you're going to have people pulling into the gap in front of you all the time. o_O
So you're then having to back off from them......repeat ad nauseum.:sick:
Also, in your scenario, I dare say the police would drop this automatic assumption that the person following is to blame (which I'm not convinced is even true anyway...).
Your dashcam would prove their brake lights weren't working.....
If it literally was always the fault of the person following, these 'crash for claim' people would always win.
Wouldn't matter if it was a deliberate attempt, using your rules, you should have been able to stop.;)
 

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judging by the long annoyed beep of the horn I had from the Audi behind me on my test drive when the motorway into Leeds goes from a 70 to 50 mph, I'm guessing that it doesnt come on until you are decelerating really quite harshly....
It's more likely he was annoyed at seeing your brake lights rather than the lack of them. Even an ICE car will slow from 70 to 50mph quite rapidly after lifting the throttle as drag is a big factor at motorway speeds. There really should be no need for braking on a motorway. Anticipation and leaving a big enough gap should allow for a steady flow. Unnecessary braking and the flash of red lights is often the cause for those stop start waves. Obviously balancing the throttle in E-Pedal will not cause the brake lights to come on, but lifting off completely surely will.
 

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It's more likely he was annoyed at seeing your brake lights rather than the lack of them. Even an ICE car will slow from 70 to 50mph quite rapidly after lifting the throttle as drag is a big factor at motorway speeds. There really should be no need for braking on a motorway. Anticipation and leaving a big enough gap should allow for a steady flow. Unnecessary braking and the flash of red lights is often the cause for those stop start waves. Obviously balancing the throttle in E-Pedal will not cause the brake lights to come on, but lifting off completely surely will.
Very good post.
Unnecessary brake lights on a motorway is very annoying.
 

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@Bol d'or Thanks. I would think that E-Pedal should be off as a general rule for motorway driving. You are unlikely to get any regeneration benefit anyway, as the car is fighting drag even on long downhill sections at motorway speeds.
 

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A bit harsh, isn't it?
I dare say there's plenty of us on here would get caught out if someone with completely inoperative brake lights suddenly slammed the anchors on....
All very well going on about safe distances etc., but real life doesn't work like that.
Sorry but I don't buy the "safe following distance is too hard in the real world" argument. Just because nearly everyone ignores this critical aspect of driving safely doesn't make it right or socially acceptable. I drive on the motorway every single day to get to work and back, so I see it all.

If everyone else jumped off a cliff would you follow too ? The vast majority of accidents and near misses on motorways are caused by two things - following too close, and unsafe no-look lane changes, usually accompanied by a complete lack of indicator usage.

Imagine how many fewer accidents there would be if people followed at a safe distance and performed safe lane changing complete with using their indicators as the law demands ? ;)

It annoys me a little when the police and media go on about speeding (on the open road) all the time and erect speed cameras everywhere when following distances and safe lane changing with indicators is far more critical for safety. Doing 85 mph on a not too busy motorway in the fast lane is generally not dangerous, but tailgating and cutting between lanes suddenly without indication is extremely dangerous and causes lots of near misses.

With regen braking we're not talking about slamming on the anchors anyway, my point was to say that even if the car in front of you did slam on the anchors with non functional brake lights you should still be able to stop in time - otherwise you're following too close. And by that standard, regen braking without brake lights should not be a concern for anyone at a safe distance behind as it is of a similar level to engine braking on most EV's at motorway speeds. (Regen braking gets weaker as speeds increase once you reach the maximum kW regen limit)
Try leaving what the highway code probably considers a safe distance on a motorway and you're going to have people pulling into the gap in front of you all the time. o_O

So you're then having to back off from them......repeat ad nauseum.:sick:
I don't need to try it, I drive on the motorway every day, and I keep back to a safe distance - probably not the full recommended safe distance but at least twice what I see most people around me doing, and yes, people keep filtering into the lane in front of me and I have to back off again to keep a safe distance.

But you know what ? I don't mind, and for the vast majority of the time I have a much bigger, safer following distance than almost everyone around me. What exactly is the problem with someone pulling into a gap in front of you ? Just back off a bit again. If a single car filling the gap makes your following distance unsafe you were still too close!
Also, in your scenario, I dare say the police would drop this automatic assumption that the person following is to blame (which I'm not convinced is even true anyway...).
Your dashcam would prove their brake lights weren't working.....
But doesn't excuse you for following too close and not being able to stop in time because of it. I went through a phase of watching all the Russian dashcam crash compilation videos so I've seen every possible way that accidents happen probably 100x over, and its very instructive. It's also pretty annoying just how many of the crashes were caused by people not paying attention...
If it literally was always the fault of the person following, these 'crash for claim' people would always win.
Wouldn't matter if it was a deliberate attempt, using your rules, you should have been able to stop.;)
Not quite as simple as that. Most crash for claim incidents - and yes, I've seen a lot of those on dashcam compilations too, involve a car cutting into the lane immediately in front of you and braking hard.

Being in the wrong for following too close only applies if the car in front of you was in the same lane for a reasonable amount of time. If someone is in an adjacent lane to you and only just in front of you and pulls into the lane immediately in front of you without warning and thus eliminates your safe following distance and then brakes and you hit them, anyone with some sense will see that the following car is not at fault, and a dashcam will save the day here.

That is a completely different situation to one where you are following a car in the same lane as yourself and you have allowed the gap to close up to an unsafe gap because you are not maintaining a safe distance. And when someone does change lanes to move in front of you and they are a bit close for comfort you should immediately back off. I certainly do.
 

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Not quite as simple as that. Most crash for claim incidents - and yes, I've seen a lot of those on dashcam compilations too, involve a car cutting into the lane immediately in front of you and braking hard.
I've seen plenty where the car isn't suddenly appearing in your lane.
Using your argument, always your fault if you run into them.
 

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Sorry but I don't buy the "safe following distance is too hard in the real world" argument. Just because nearly everyone ignores this critical aspect of driving safely doesn't make it right or socially acceptable. I drive on the motorway every single day to get to work and back, so I see it all.

If everyone else jumped off a cliff would you follow too ? The vast majority of accidents and near misses on motorways are caused by two things - following too close, and unsafe no-look lane changes, usually accompanied by a complete lack of indicator usage.

Imagine how many fewer accidents there would be if people followed at a safe distance and performed safe lane changing complete with using their indicators as the law demands ? ;)

It annoys me a little when the police and media go on about speeding (on the open road) all the time and erect speed cameras everywhere when following distances and safe lane changing with indicators is far more critical for safety. Doing 85 mph on a not too busy motorway in the fast lane is generally not dangerous, but tailgating and cutting between lanes suddenly without indication is extremely dangerous and causes lots of near misses.

With regen braking we're not talking about slamming on the anchors anyway, my point was to say that even if the car in front of you did slam on the anchors with non functional brake lights you should still be able to stop in time - otherwise you're following too close. And by that standard, regen braking without brake lights should not be a concern for anyone at a safe distance behind as it is of a similar level to engine braking on most EV's at motorway speeds. (Regen braking gets weaker as speeds increase once you reach the maximum kW regen limit)

I don't need to try it, I drive on the motorway every day, and I keep back to a safe distance - probably not the full recommended safe distance but at least twice what I see most people around me doing, and yes, people keep filtering into the lane in front of me and I have to back off again to keep a safe distance.

But you know what ? I don't mind, and for the vast majority of the time I have a much bigger, safer following distance than almost everyone around me. What exactly is the problem with someone pulling into a gap in front of you ? Just back off a bit again. If a single car filling the gap makes your following distance unsafe you were still too close!

But doesn't excuse you for following too close and not being able to stop in time because of it. I went through a phase of watching all the Russian dashcam crash compilation videos so I've seen every possible way that accidents happen probably 100x over, and its very instructive. It's also pretty annoying just how many of the crashes were caused by people not paying attention...

Not quite as simple as that. Most crash for claim incidents - and yes, I've seen a lot of those on dashcam compilations too, involve a car cutting into the lane immediately in front of you and braking hard.

Being in the wrong for following too close only applies if the car in front of you was in the same lane for a reasonable amount of time. If someone is in an adjacent lane to you and only just in front of you and pulls into the lane immediately in front of you without warning and thus eliminates your safe following distance and then brakes and you hit them, anyone with some sense will see that the following car is not at fault, and a dashcam will save the day here.

That is a completely different situation to one where you are following a car in the same lane as yourself and you have allowed the gap to close up to an unsafe gap because you are not maintaining a safe distance. And when someone does change lanes to move in front of you and they are a bit close for comfort you should immediately back off. I certainly do.
Well said, I agree with every word.
 

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Some motorways such a the M62 have chevrons marked on the road and notices state to keep two of those between you and the vehicle in front. Most people drive much closer.
The recognised gap to keep is two seconds to allow time for reacting. To check that count two seconds after the vehicle in front passes a certain feature until you pass it too.

I'd presume the new Leaf has been designed with lighting that meets legislation requirements.
All very well going on about safe distances etc., but real life doesn't work like that.
Try leaving what the highway code probably considers a safe distance on a motorway and you're going to have people pulling into the gap in front of you all the time. o_O
So you're then having to back off from them......repeat ad nauseum.:sick:
The driving law you might not know that will land you with a £100 fine and three points
 

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Try leaving what the highway code probably considers a safe distance on a motorway and you're going to have people pulling into the gap in front of you all the time. So you're then having to back off from them......repeat ad nauseum.
That is annoying for sure. But if you think about it, if say ten cars did that to you in a twenty miles motorway trip then you would still only be ten car lengths further back down the road than you would have been by closing the gap to prevent it. And ten car lengths at motorway speeds would only make you a few seconds late in your trip. Driving too close has the potential to make you very late indeed. I prefer to get there safely, even if that means15 seconds later.

I would think that E-Pedal should be off as a general rule for motorway driving. You are unlikely to get any regeneration benefit anyway, as the car is fighting drag even on long downhill sections at motorway speeds.
I agree. Motorway driving should probably be entirely in D to allow minimum regeneration, and maximum coasting. That could also encourage a higher level of anticipation and avoid harsh changes in speed which in itself would help safety.
 
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