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Discussion Starter · #1 ·
Does anyone else find the brakes on the Kona EV to be WAY to agressive and non-liniear?
I drive mostly commute and the traffic and start and stop quickly.

Yesterday the traffic came to a stop, I pushed the brakes (firm but not panic) and the tires locked up. It even seemed that they wouldn't "unlock" until I hit the accelerator.
Scared the you know what out of me.

Anyone else?

I also find I spend a tremendous amount of micro corrections in the steering to stay centered in the road. It's not alignment as it isn't biased to one side.
 

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Does anyone else find the brakes on the Kona EV to be WAY to agressive and non-liniear?
I drive mostly commute and the traffic and start and stop quickly.

Yesterday the traffic came to a stop, I pushed the brakes (firm but not panic) and the tires locked up. It even seemed that they wouldn't "unlock" until I hit the accelerator.
Scared the you know what out of me.

Anyone else?

I also find I spend a tremendous amount of micro corrections in the steering to stay centered in the road. It's not alignment as it isn't biased to one side.

Sounds like typical ABS/regenerative braking feeling.
 

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Discussion Starter · #3 ·
@fastKona, I would usually agree. However, I have two other electric cars and this definatley seems more agressive. Plus I wouldn't have expected them to stay "locked up" even after your foot is removed from the brake pedal.
 

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I find the brakes to be “grabby” when first applied, overly sensitive at top of travel, but then becomes linear in feel.. especially when cold. The non-EV kona..
 

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I find the brakes non-linear only in the few moments before coming to a stop. I hope Hyundai's next model refresh manages to fix that plus the annoying click when the EPB activates and releases.
 

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This pertains to the Kone EV:

I find this also. The pedal definitely grabs unreasonably hard, and impossible to modulate during hard braking.

OTOH The "left side paddle", when held, will aggressively brake ( I think regen braking) but it is pretty linear.

Unfortunately, braking with the paddle has a problem: It is disabled when cruise control is active.
You have to remember to cancel cruise control before you can brake with the paddle.

It is dangerous and stupid to make any brake work this way.

Even the lightest tap on the brake pedal immediately turns off cruise control, so the cruise control
never impedes braking. This is a sane, well understood, intuitive model. Why deviate from this?
That is exactly how the left paddle braking hold should work.
 

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Does anyone else find the brakes on the Kona EV to be WAY to agressive and non-liniear? I drive mostly commute and the traffic and start and stop quickly. Yesterday the traffic came to a stop, I pushed the brakes (firm but not panic) and the tires locked up. It even seemed that they wouldn't "unlock" until I hit the accelerator. Scared the you know what out of me. Anyone else?
Been there right with you. Happend to me 3 times now in 18 months. Scared the same thing out of me. Rediculous. The way I see it, it's programmed that if you hit ANY amount of break WHILE it's not happy with the closing rate of change (the audio beeping also sounded each of the 3 times), bam, full AB lock-up. No feathering as you were thinking you were doing. Sucks. Hate it. Dangerous in it's own right. Two of those three times the car behind me also had to lock up and both times they did not hit me. The other time no one was behind me. Not happy with their programming of it. I did not see any of them as needing that kind of response given the distance I still had between me and the car in front of me and my speed (dry road conditions). Only solution I see is to leave more distance in front of me (a good thing of course but on the California - and probably most - freeways, any spot you leave in front of you gets filled quickly and your back to the same situation).
 

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Just happened to me 2 days ago, front hopped a bit and the brakes appeared to lock up momentarily.
 

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The car seems to have some rough edges, when it comes to user experience, Hyundai has some distance to cover here.
They seem to come close, but the final touches are often missing. Just my overall impression, they appear to me
a bit sloppy at times on these subtle details, like they have not given it a lot of thought, just slapped some random solution
in place and called it done.

My previous cat was a Mercedes. We can say many bad things about German luxury cars
(annoying, greedy dealers and spotty reliability top the list) but their user experience is dialed in for sure.
Those cars just do what you would expect most of the time. I almost never had to scratch my had about
"Why does the car do X instead of Y what I would expect?".

I am working in software, and we have a user interface concept called "The principle of least astonishment".
Meaning software should always behave in a manner that astonishes the user the least.
I think this is a good principle for laying out a vehicle 's functions/behavior.

For the Kona EVi. I can come up with a short {probably incomplete) list of my top offenders:

-Brake modulation : "what the heck?"
-Paddle braking Make it always work, (like the brake pedal does. turn off cruise control if it is on)
-Charging port behavior when charge is incomplete
It needs a button somewhere on the dash "Stop charging" or "Unlock Charge port". Would this not make sense to anybody?
Yes there is a trick that works, but no that is not something you would easily figure our if you do not know.
-Lane keeping assist behavior: A real head scratcher.
It has a hard to hear, insignificant beep telling you to put your hand on the wheel, but no audible warning when it actually disables
the lka (where you would _really need to know the car is no longer steering for you and you may run off the road)
-Put the car in "park" if the driver's door is opened when the car is not moving.
 

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With the current state of design it's not a good idea to mix left-paddle hold with foot braking. The system has to deal with the complexities of fore-aft braking balance between the hydraulics and front-only regen, which the pedal manages to do on its own reasonably well. I'd be quite happy to see the paddle hold feature go away as I think it's a poorly-executed gimmick. However there is no question that the Hyundai/Kia EV base technology will continually evolve throughout the various models.
 

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Kiwi:

I was unaware of the front-only nature of regen braking...
Now that I think of it it makes sense since the car is fwd, and the motor does the regen braking (right?)

From a naive user perspective, the paddle seems useful, it does something that the pedal does rather poorly.
Non emergency, aggressive, modulated modulated braking.

The paddle seems to do be more effective than just letting the accelerator up. (even at level 3 regen) .
If the paddle played nicer with cruise control, it would be a good way to fill the above role.

If the foot brake worked better, (more modulated, like on a typical ICE car) I could care less about the paddle.
And, in an emergency, I would just slam the pedal, and would not care that the wheels lock up.
Let the ABS do its thing. But that should not be a common occurrence.

Seems like there is a whole in the braking design.
There is: weak, decelerator activated regen braking and lock up prone brake pedal, and nothing in-between.
It is one of the flaws of this car that I find more annoying as time passes.

Locking up my wheels when I am merely slowing down from highway speed to exit ramp speed is just rude
and annoying.
 

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I understand why they made the paddle work the way it does. Regen braking is primarily activated by the accelerator pedal (by letting it up).
They modeled the behavior by putting the function into the wrong object class. It "inherited" the behavior from the accelerator,
and it should have inherited its behavior from the brake pedal.
I argue most people would classify it into the 2nd class not the first.

The association with the first class is superficial (both involve regen braking)

The strong and well thought through association is: (It is a deliberate, single purpose braking action) .
How the braking function is actually implemented is coincidental here.

Disabling accelerator activated regen braking makes sense when cruise control is on, because the way cruise control is defined
The essence of cruise control is to maintain the set speed while you can take your foot off the accelerator.

But when regen braking is activated by paddle the same is not true because holding the paddle is a single purpose
clear action,(it only communicates that we want to slow down).
I argue this behavior is just like the brake pedal behavior,. It would be more intuitive to model it on that.

To correct this, all they need to do is disable cruise control when the paddle is held. All the problems Kiwi is referring to
(braking force is front wheels only in this case, presumably in an emergency it may spin the car out)
This hazard, if there is indeed one, is already present. and have to be deal with somehow.

I can just turn off the cruise control via the steering wheel controls, or tap the brake pedal
at high speed, and activate the 'front-wheels only" regen braking via the paddle.
All possible baddness resulting from this there,
so turning off the cruise control surely would not introduce anything new here.
 

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Even without cruise control I see it now and again if I left-paddle-hold and add the foot brake because I underestimated the stopping distance. I also see it under foot braking alone, coincident with uneven, rippled road surfaces caused by trucks on approach to stops.

Interesting analogies with OOP as I spent a decade designing servo controlled industrial equipment as an ME with my colleague's from electrical and software disciplines. In those terms the brake pedal applies what appears to be a (negative) torque-demand proportional to the requested braking force while the left paddle (being only an on/off switch) initiates a fixed deceleration profile, requiring the driver to mentally integrate the distance covered to avoid overrunning the expected stopping point.

The problem appears to be that the foot brake system does not respond as fast as we all might like under changing road surface conditions. I have to wonder how other EVs cope, as all have similar goals to optimise available regen under braking. Given the mechanical complexity and related potential time lag in the Kona/eNiro's braking system, I'm not surprised at this shortcoming. I've seen many examples in industrial control where the mechanicals has insufficient bandwidth to support the required performance and I suspect this is just another case of that.
 

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BTW. I discovered today, that the Kona EV actually does the right / logical thing if the driver 's door is opened while the car is in forward or reverse and being held by the bake pedal.
Opening the door actually puts the car in "park". But not if the car is moving.

I missed that, because the switching to "park" will happen when I take my foot off the brake pedal.

So: Kudos to Hyundai, for getting this behavior right!

In fact, it Hyundai implemented this better than the MB Cla 250, (On the MB shifting to "park" may happen even if the car is moving which
may cause some obvious problems. .

Another note: Normal, "gas pedal" activated regen braking has only 3 available levels: 1, 2, and 3 (configurable) . But, the car actually has 6 regen braking levels. Levels 4,5, and 6 can only activated via the left paddle.Tthe higher levels are only used when the car is moving fast enough. This is evident from the display, which indicates the level of regen braking applied.
I was messing with the paddle and observing the energy backflow meter on the dash. The paddle has an useful braking function, that is not duplicated/accessible by any other method.

Since the paddle is not something I would rely on in an emergency, I think I can live with "oh well, if cruise control is on, you have to turn that off first", although I
reserve the right to be annoyed. :) .

The hydraulic brakes will grab rather horribly. Reminds me of aiir brakes I on rental trucks. I am seriously thinking about switching out the brake pads to see if I can make this
a bit better. Anybody tried that?
 

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OK, so I notice that when braking with the break pedal, all levels of regen braking are activated (all 6 of them, if I go fast enough).
So the good news is that all available levels of regen braking can be activated purely by brake pedal modulation, and the
steering wheel paddle is not really necessary.

As we press the pedal harder, eventually the hydraulic brake system kicks in. The transition between regen and hydraulic braking is not smooth,
which is why the foot pedal tends to grab so abruptly.
 

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Been there right with you. Happend to me 3 times now in 18 months. Scared the same thing out of me. Rediculous. The way I see it, it's programmed that if you hit ANY amount of break WHILE it's not happy with the closing rate of change (the audio beeping also sounded each of the 3 times), bam, full AB lock-up. No feathering as you were thinking you were doing. Sucks. Hate it. Dangerous in it's own right. Two of those three times the car behind me also had to lock up and both times they did not hit me. The other time no one was behind me. Not happy with their programming of it. I did not see any of them as needing that kind of response given the distance I still had between me and the car in front of me and my speed (dry road conditions). Only solution I see is to leave more distance in front of me (a good thing of course but on the California - and probably most - freeways, any spot you leave in front of you gets filled quickly and your back to the same situation).

More of Hyundai smitty coding with lack of perfectionism and short testing.
 

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I reckon the closing rate is something you can control most of the time. Just do not come up on the car in front of you too fast.
If it is an emergency, and the guy in front of you slammed on the brakes, you can argue there is not better choice than locking up your abs.
In all honesty, the subtleties are hard to get right, and Hyundai gotten a lot better over the years.
My complaint was, when I just tool around, with no other car in sight, and step on the brake, it would grab unreasonably. There is very little modulation possible, once the hydraulics kick in.

There always seems to be a bit of "vagueness" in Hyundai's approach. My pet peeve that they do not publish detailed and precise maintenance specs. For example: what is the list of approved spark plugs (per engine) ? Anti seize lube or no? What is the exact torque to use for a new plug? Or a re-installed plug? They do not publish detailed "oil specs" per engine, even Fiat publishes those nowadays.
 
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