Starting with full charge, downhill for 2 miles, engine comes on

[2002]

I perceive it that I am using friction brakes more than I would not have previously. Perhaps I'm actually not and its all regen just with a pedal and brake lights - guess as a data nerd I'd be interested to know.

If it's anything like the Prius which I am more familiar with the friction brakes are used only under 5 mph or in hard stops. I am new to Clarity but expect that even though it's a heavier car the friction brakes are also not used much in normal driving. In fact I posted a previous thread that when I was at the dealer last week test driving my new Clarity there was a ticking noise that turned out to be brake rust that normal stopping wasn't clearing https://insideevsforum.com/community/index.php?threads/ticking-noise-in-ev.5461/

I agree that with traffic around it's safer to slow down at a normal pace. But when no one is behind you a long slow coast is best, because then you are being slowed mainly by the unavoidable and ever present wind resistance, tire friction and mechanical friction, along with a small amount of regen that is provided to add some "normalcy" to the slowdown.

One of the problems with not using much of the brake pedal is not having the brake light turn on to warn the car behind that you are slowing down. Could cause an accident if the person behind is not paying attention.

I wish the brake light would turn on, if you go beyond a certain Regen level.

I agree, although maybe it does at certain levels, it's nearly impossible to tell. If it doesn't for regen I think it does for ACC braking. Either way I have always felt there should be a brake light indicator on any car that can automatically turn on the brake lights. That's because the brake lights are a signal to other drivers and I should always know when I am signaling. I know when my turn signals are on, emergency flashers, and reverse lights, for the obvious reason that I am the one who initiated it, but also because for all them there is some kind of indicator. Cars don't have brake light indicators but you already know that even slight pressure on the brake pedal activates the light. But in a car like the Clarity that can activate the brake lights itself I have no idea. Although I do get a "Braking" message on the dash at times and probably that coincides with brake light activation, but I have no way to know if the brake lights come on at other times. I am seriously planning to temporarily rig up a piece of foil or something over a small portion of the third brake light so that I can do a test drive at night and (safely) observe through the rear view mirror when the brake lights come on. Although I don't know of a way to safely activate automatic braking. I know some people make a Don Quixote like charge at a cardboard box in an empty parking lot but I have no intention of doing that.

 

[vin seeram]

that makes sense for prolonged and/or significant declines in order to avoid overheating brakes on a pass out of Colorado.

That relates to my gripe. It would have been nice to be able to force engine breaking irrespective of battery SOC in those situations of prolonged down slopes.

 

[insightman]

Hmm. Perhaps I'd argue (starting to feel like a lawyer) that makes sense for prolonged and/or significant declines in order to avoid overheating brakes on a pass out of Colorado, but not in my instance for sake of argument here of 2 consecutive stops in short distance from call it 30mph. In those situations, it forces the first call it 4 miles give or take of my daily commute to be with ICE. If by chance I made the return trip and had the same issue, in theory, my round trip commute for the day would be 100% ICE haha.

When you apply the brakes, the Clarity PHEV doesn't know whether you'll be pressing the pedal for a second or an hour.

 

[insightman]

I am seriously planning to temporarily rig up a piece of foil or something over a small portion of the third brake light so that I can do a test drive at night and (safely) observe through the rear view mirror when the brake lights come on.

That's easier than what I kept putting off: Wiring a beeper into the brake-light circuit.

 

[insightman]

That relates to my gripe. It would have been nice to be able to force engine breaking irrespective of battery SOC in those situations of prolonged down slopes.

A BEV, with its much larger battery can afford to allow "one-foot braking." The Clarity PHEV, however, has a much smaller battery so a regen level that would enable one-foot braking could quickly result in a fully charged battery--especially because Clarity PHEVs often start out a trip with a fully charged battery. So the high level of regen that would make one-foot braking possible would not be available most of the time unless Honda amped up the Clarity PHEV's battle between the ICE and the starter motor/generator to an "angry bees" level of electrical (and gasoline) wastage.

Also, consistency in braking is very important for safe driving, so having one-foot braking available when the SoC is low, but not when the SoC is high would constitute a safety hazard. The Collision Mitigation Braking System would get quite a workout from drivers who counted on a one-foot braking level of regen only to discover that the previous application of one-foot braking brought the battery to a full SoC.

 

[thecompdude]

A BEV, with its much larger battery can afford to allow "one-foot braking." The Clarity PHEV, however, has a much smaller battery so a regen level that would enable one-foot braking could quickly result in a fully charged battery--especially because Clarity PHEVs often start out a trip with a fully charged battery. So the high level of regen that would make one-foot braking possible would not be available most of the time unless Honda amped up the Clarity PHEV's battle between the ICE and the starter motor/generator to an "angry bees" level of electrical (and gasoline) wastage.

Also, consistency in braking is very important for safe driving, so having one-foot braking available when the SoC is low, but not when the SoC is high would constitute a safety hazard. The Collision Mitigation Braking System would get quite a workout from drivers who counted on a one-foot braking level of regen only to discover that the last instance of one-foot braking brought the battery to a full SoC.

Even Teslas don't allow Regen braking when the battery is full. Someone had posted a tweet from Musk about it a few weeks ago. Or when the battery pack is too cold or too hot, Regen will be limited.


Also, I am not sure if there are constraints related to the rate of charge. I am not sure if the Clarity EV supports fast charging. But the other EVs support it and the Clarity PHEV does not. So not sure whether that also plays into the equation, as heavy Regen braking will deliver a lot of energy to the battery in a short period of time.

 

[The Gadgeteer]

One of the problems with not using much of the brake pedal is not having the brake light turn on to warn the car behind that you are slowing down. Could cause an accident if the person behind is not paying attention.

I wish the brake light would turn on, if you go beyond a certain Regen level.

I usually tap the foot brake ever so lightly to activate the brake lights whenever I do any sudden or heavy regen for that exact reason. It is an automatic habit for me now but I wouldn’t mind if the car did it on its own. Perhaps flash the brake lights for a second for every chevron activated.

 

[2002]

That's easier than what I kept putting off: Wiring a beeper into the brake-light circuit.

Actually something more permanent would be nice although I would prefer a small LED light rather than a noise. Then again it may turn out that the large orange "Brake" warning that displays on the dash coincides with all automatic brake light activation, although the manual is a big vague on this.

This is the "Brake" message I am referring to, although it's not clear from the manual if this message is always associated with CMBS and ACC brake activation. In other words can this message sometimes appear even when the system is not applying the brakes?

In the ACC section it mentions that the brake lights are activated when the brakes are applied by ACC

But will this always cause the "Brake" warning message flash?

No mention about brake lights in the CBMS section but it's hard to imagine that it doesn't activate the brake lights when it applies the brakes.

No mention that I could find about paddle regen activating the brake lights, so my guess is that it doesn't.

 

[insightman]

I am not sure if the Clarity EV supports fast charging.

Both the Clarity Electric and the Japanese-market Clarity Plug-In Hybrid have fast-charge DC ports.