Does regen activate the brake lights?

Boosterspice

Boosterspice

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I worry that some dink on their phone is not going to notice I'm slowing down. Just ordered the blackvue with rear cam just in case.
 
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By using the paddles, not that I have seen, and I have checked several times.

It won't engage the 4th chevron above 56-57 mph either.

I think it would make sense for the lights to come on with 3 or 4 chevrons of paddle regeneration; but, that doesn't seem to be the design.

When regenerating with brake pedal, the lights definitely come on.

Sent from my SM-N960U using Inside EVs mobile app
 
I've read somewhere that the brake lights do come on with regen when there's sufficiently-rapid deceleration (makes sense, though one could argue with Honda about where that threshold should be).
 
ClarityDoc said:
I've read somewhere that the brake lights do come on with regen when there's sufficiently-rapid deceleration (makes sense, though one could argue with Honda about where that threshold should be).
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I'll turn on the side cam and test it next time I drive in the dark, I don't very often. Also seems like my regen does not reach max effectiveness until I've gone a couple miles (Sport, 4 chevrons always)
 
Candice reported regen brake lights at night here: https://insideevsforum.com/community/index.php?threads/regenerative-paddles.2897/page-2#post-31386

There are a lot of threads if you search something like regen lights.

I've used reflective signs on low traffic roads to test when brake lights come on, but I've gone through so many different EVs in my recent past; I cannot remember anymore what was Volt-1, Volt-2, Bolt, or Clarity (my favorite, so far).

I was thinking just today, it would be nice if there were a little non-intrusive red dot on the driver display to show when the brake lights are on. I've often thought of a dim light pipe (or a small LED set dim) somewhere in the rear windows, but never get to it.
 
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I'm going to need to test this. I was driving home late at night earlier this week on a very dark Road with no other cars. I swear I didn't see the brake lights other than when I physically touched the brakes. Will test next time my wife takes me for a charge.
 
I've tested this several times at night on a straight road with almost no lighting so I could see the rear. At about 45 mph, I put all four chevrons and no brake lights at all. As soon as I touched the pedal, they came on.
 
I’ve made the analogy of regen and downshifting in a manual transmission car. On twisty roads the effects are quite similar.

My point is, we don’t tend to concern ourselves excessively about no brake lights coming on when we downshift to slow down. Not sure how regen braking, especially at the modest level even 4 chevrons provide, is all that different.

Pretty sure I’m not the first to point this out.
 
X2 to Fast Eddies comments. Paddle braking is pretty weak from any speed, even at the 4th pull. Downshifting from speed in my last manual tranny 04 GTO could briefly chirp the rear tires at times (rwd car)...and in my current manual tranny Mazdaspeed 3 downshifting can slow that car MUCH more aggressively than the very mild Clarity ever does with a paddle from any speed. And an alert aggressive manual tranny driver would never pull such hard downshift maneuvers with someone on his or her bumper unless on the race track. So Clarity simply doesn’t need brake lights with paddle IMO. It would be like crying wolf for a lot of people if the brake lights went on every time they pulled the paddle. This car is way too conservatively programmed for regen braking to warrant brake lights.

But all that said, if you’re in a situation where you are driving Clarity and want to activate your brake lights, it’s as simple as lightly stepping on the pedal, as you should and would in every other car. This guarantees lights are on. Foot off pedal? Assume brake lights are not on. It really is that simple in my mind.

Tailgaters have always existed, and always will. And drivers still gotta drive. This car is not all that different...
 
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We all got to deal with a lot of tailgaters. I watch my use of the regen paddles when I have a 'gater behind me. I drive a lot before dawn, and I have never noticed my brake lights coming on even at 4 chevrons of regen.

I know that I've seen a lot of front ends diving because they aren't paying attention to me slowing down.
 
I am in the habit of ever so lightly tapping my brakes so the lights go on when I do heavy regen. I am of the belief the first little bit of travel on the brake peddle doesn’t kick in the friction brakes anyway.
 
The Gadgeteer said:
I am of the belief the first little bit of travel on the brake peddle doesn’t kick in the friction brakes anyway.
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I would say much more than the first little bit, based on the charge indicator when stepping on the brakes. Anyway why would the car activate the friction brakes when regen is available? We know from using the paddles at four chevrons that regen is at least that strong, and even stronger when using the brake pedals based on the charge indicator. Only when regen is maxed out would it need to use the friction brakes, why would it use them any other time? Except in the last few mph since regen apparently isn't smooth below 5 mph or whatever the cutoff is (that was Prius I don't know about Clarity). The only other time would be when the battery is full, although apparently in some of those cases it uses ICE to slowdown in addition to friction brakes.

craze1cars said:
Foot off pedal? Assume brake lights are not on. It really is that simple in my mind.
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Except that the manual states that ACC will activate the brake lights, although we don't know at what threshold.

Fast Eddie B said:
we don’t tend to concern ourselves excessively about no brake lights coming on when we downshift to slow down.
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Well maybe we should. In the past cars didn't have the technology to activate the brake lights when downshifting. And back then cars didn't have airbags, ABS etc. not because they didn't exist, but because the mindset was different. Go back to the 1950's and besides no seatbelts (except as an option) if a collision threw you against the non-collapsing steering wheel, or through the non-laminated windshield, you were pretty much a goner. But this was pretty much all accepted. We live in a more safety conscious world now compared to then (except drivers are no better and maybe worse but that's a separate topic)

The last major change to brake lights that I am aware of was the third brake light back in the 1980's. I think the NHTSA is overdue in evaluating brake light activation. Tapping on the brakes to deactivate cruise control (which I never do but many people do) should not activate the brake lights and cause a reaction from the car behind that can result in unnecessary traffic slowdown or even worse. And heavy regen or downshifting should activate the brake lights. But when? That's what they need to determine, some type of standard that differentiates normal gradual slowing and more sudden slowing. Then mandate that brake lights activate at that threshold. Whether that is done through accelerometers (like most Smart phones now have) or through instantaneous wheel speed calculation (like ABS has been doing for years) that can be decided by each car manufacturer how they do it, as long as it meets the standard. The technology to do this would be almost child's play compared to LKA and ACC, so no reason they can't do it, the only hard part probably would be deciding and agreeing on the braking threshold. While they are at it, they could come up with an additional threshhold for hard braking which will cause the brake lights to flash, as seen in some aftermarket applications although those flash all the time. So gradual slowing or light tap on the brakes - no brake lights. Heavier slowing, however it occurs - brake lights. Hard braking - flashing brake lights.
 
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I agree that technology exists to activate brake light above a certain level of deceleration.

I further agree it would be a good idea and enhance safety. Especially in a car with higher levels of regen available. Certainly one that allowed true “one pedal” driving.

That said, in our Clarity’s I don’t think lack of brake lights when using regen is a huge safety concern given the moderate deceleration even 4 chevrons provide.
 
Test: slow down at 4 chevrons then lightly apply brake pedal.
Observation: Charge indicator displays greater regen charging.
Conclusion: Not only does the first little bit of brake pedal travel provide regen it is secretly the “5th chevron” by providing more regen than 4 chevrons.
 
The Gadgeteer said:
Test: slow down at 4 chevrons then lightly apply brake pedal.
Observation: Charge indicator displays greater regen charging.
Conclusion: Not only does the first little bit of brake pedal travel provide regen it is secretly the “5th chevron” by providing more regen than 4 chevrons.
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Exactly. And it's a secret because unfortunately Honda mentions nothing about this in the owners manual creating a lot of confusion.

You should try the other test I was describing, don't apply the paddles just press on the brakes and you can get to that same level of regen charging, and even more.
 
Exactly....and this is why I always said and still think the paddles are largely gimmick. The brake pedal does the same thing, and more. More regen, no more “brake light anxiety”... One notable exception where I feel the paddles do have great merit is descending mountains...miles long grades where you’re trying to stop gravity acceleration. Much like when you would normally downshift any other car. Paddles shine here. And only here. But using them around town has always been silly and pointless to me. Just drive normal. And yes I know others disagree and will now expunge the merits of paddling around town. But everyone knows that my opinion is the only correct one, and all other opinions are incorrect... so neener neener phtphffffft.

Take THAT, all you silly interweb disagreeers...
 
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craze1cars said:
Paddle braking is pretty weak from any speed, even at the 4th pull
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Yup. Using "L gear" in my C-Max delivers greater decel than the Clarity's full regen and even that doesn't activate brake lights. Anyone who's driven a manual transmission can slow greater than either of these cars by downshifting one gear too many.

There's actually a DOT reg. for the level of decel needed to require the activation of brake lights but, sorry, I don't have a link. Our Subaru has a car icon in the drivers display that shows the brake lights when the brakes are used in ACC mode.
 
fotomoto said:
There's actually a DOT reg. for the level of decel needed to require the activation of brake lights but, sorry, I don't have a link.
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Do you remember if it includes downshifting in manual transmission cars, or is the requirement only for automatic systems?
 
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