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I recently purchased the 2020 CRV Hybrid EXL, and I am really enjoying it - very comfortable, quiet and fun to drive. This is my first hybrid and I am trying to learn how to optimize the fuel mileage by taking advantage of the driving feedback tools. Does anyone know if the deceleration paddles on the steering wheel are different than the regenerative braking system? I have been using the paddles to adjust cruising speed or to slow down from a distance away when approaching a stop sign or traffic light, thinking that this may save wear-and-tear on the brakes. But not sure if that makes sense - are these different systems or the same braking system that can be activated in two different ways? (I have noticed pressing the brakes is required to stop if approaching at too high of speed, so they are not completely the same). Under what conditions would one use one system over the other?
 

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I recently purchased the 2020 CRV Hybrid EXL, and I am really enjoying it - very comfortable, quiet and fun to drive. This is my first hybrid and I am trying to learn how to optimize the fuel mileage by taking advantage of the driving feedback tools. Does anyone know if the deceleration paddles on the steering wheel are different than the regenerative braking system?
Yes and no. The short answer is that the paddles change how much regenerative braking is performed when you are not pressing either the gas pedal or the brake pedal. It still happens when you then press the brakes, but they pretty much override the effect of the paddles.

Honda's iMMD hybrids use what is called "brake-by-wire." That means that the brake pedal is not actually connected to any form of brakes. It is connected to a computer. The computer decides, based on how hard you are pressing the pedal and how fast you are going, how much braking to apply with what you called "the regenerative braking system," and how much to apply with the front and/or rear friction brakes.

But conventional cars have another form of braking, called engine braking. When you take your foot off of the gas pedal, the engine is still connected to the wheels but no gas is pumped into them. The action of compressing the empty chambers slows the car a little bit. You can shift into a lower gear to increase this effect.

Many people may not realize how this is happening, but they still expect result. But in your iMMD hybrid, the gas engine will not be connected to the wheels this way, so it can't do conventional engine braking. Instead, the traction motor is used as a generator to produce the same result, simulating what engine braking would do. The generated electricity is sent to the battery.

There are four levels of this simulated engine braking, as indicagted by the number of chevron symbols ("v"). Zero symbols is the same as one. The main point of using the paddles is that no friction brakes will be used until you press the brake pedal.
 

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There are four levels of this simulated engine braking, as indicated by the number of chevron symbols ("v"). Zero symbols is the same as one. The main point of using the paddles is that no friction brakes will be used until you press the brake pedal.

If the brake lights are not activated by using the paddles when approaching a stop sign or traffic light, should one then not use the paddles in this instance as no indication is given to a reduction of your cars speed to a following car? Are there other occasions when no brake lights appearing on your car while using only paddles for a speed reduction might cause rear-enders? Using paddles may save brakes pads but at what cost of an accident? Sounds good but !
 

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I am not familiar with the paddle system on the CR-V Hybrid, but I am on the 19 Acura RDX I own. In the RDX, using the paddles to slow the vehicle is just the same as if the driver was downshifting a manual transmission. NO brake lights come on.

In the CRV Hybrid, (my little understanding is) you can NOT come to a complete stop using the paddles, so a brake pedal application is required, and then the brake lights will come on.
 

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Good point but in real time the rate of deceleration using regen paddles is much less than braking so we're not talking about rapid loss of speed or unexpected stopping on the highway. If you get rear ended it's unlikely to be caused by using the paddles to slow down, more likely the driver behind you wasn't paying attention.
 

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1998 CR-V EX 4spd auto "Big Green" completely stock with roof rack and front mud flaps
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JeffJo, you sure about having no mechanical connection to the friction brakes? That sounds illegal and unsafe to drive without a functioning backup in the event of a computer failure. Even non-hybrids have a failsafe hydraulic breaking system in case one of the brakes or brake lines fails.
 

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I rarely use any sort of braking other than the brakes.

Brakes are relatively cheap and easy to replace compared any of the other components involved in slowing the vehicle down. Why put extra wear expensive and difficult to repair components.

Regenerative braking, with the brake pedal, appears to charge my Ford hybrid batteries much faster than anything else.
 

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If the brake lights are not activated by using the paddles when approaching a stop sign or traffic light, should one then not use the paddles in this instance as no indication is given to a reduction of your cars speed to a following car?
Regen braking effort decreases with speed, and actually cuts out somewhere around 5 to 7 mph. So if you are slowing enough for this to be an issue, you will be using the brake pedal.

In the CRV Hybrid, (my little understanding is) you can NOT come to a complete stop using the paddles, so a brake pedal application is required, and then the brake lights will come on.
Right.
JeffJo, you sure about having no mechanical connection to the friction brakes?
Yep. There are fail safes, so it is probably safer than a mechanical connection which can break.
 

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I have the hybrid. The regen braking is never enough that you would need to warn someone with the brake lights, as someone else said, feels like downshifting a manual. And it will never bring you to a complete stop unless going up a hill. I use it a lot, mostly trying to get just the right amount of slowing down to turn a corner or slow down coming to a light or stop sign, using just the right combination of the our levels (only three in practice because the car is always in one and as soon as you hit the paddle once you are in two.)
 

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My first Ford hybrid had a poor transition from regenerative braking to normal braking.

At about 5mph you could feel the change and you may skid to stop. This was somewhat embarrassing in a parking lot. My wife though it was just me.

All the first hybrids in our fleet were like that. It had been fixed by the time I got the next one.
 

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JefJo, just so you know this type of fail-safe is always mechanical. The hydraulic brake fail-safe isn't even an extra system: it's an integrated feature of the primary hydraulic system. The cable operated brake is a secondary backup. Cars are made like that because hydraulic and mechanical systems are, and always will be, more reliable and less prone to failure than electronics.
 

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...Cars are made like that because hydraulic and mechanical systems are, and always will be, more reliable and less prone to failure than electronics.
Please provide documented proof of this claim.
I've had an accelerator cable break, leaving me without the ability to accelerate, but have yet to have a "drive by wire" system fail. A physical cable often has many friction points, providing the possibility, to wear through the cable.
 

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JefJo, just so you know this type of fail-safe is always mechanical.
????
My understanding is that the brake pedal is attached to two actuators that are read by the computer, which activates fail-safes if they do not agree with each other. Obviously, those fail-safes are mechanical, and will also activate if a fault is detected in the electronic system.

Note that the regen brakes have to be under computer control, since it has to arbitrate how power is drawn from the motor.
 

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No computer is reliable enough to be an automotive fail-safe.

Think about it, what happens if the car switches off? What happens if the fuse powering the brake control module burns out?

If your brakes fail, it's not just your butt or the line, but whatever smaller cars or pedestrians are in front of you, and Honda would be an the hook for both. Look at GM's recent recalls because of their cars switching off while driving. The brakes didn't fail on any of those cars, and it still killed people.

In conventional cars the first fail safe is that if hydraulic pressure is lost in part of the system, the master cylinder splits the brakes into two separate hydraulic systems whenever the brake pedal gets 2/3 of the way down. Each system has one front brake and the whichever rear brake is on the opposite side of the car. The emergency brake is your second fail safe.

Basically, if it can be switched off without the car being completely destroyed, it's not a fail safe.
 

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I'm still curious if anyone with actual mechanical knowledge of the CR-V hybrid knows more about the brakes. I wouldn't dare drive one, ride in one, or drive in front of one if emergency breaking actually required computer intervention.
 

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To JB is AZ, I now have my second car past 200k miles, and one past 400k miles. I have only ever seen mechanical controls break twice, and they were for secondary systems that the car does not need to operate. My 400k car is still sitting in my driveway at 39 years old, 100% of its mechanical controls still work, but that car has needed countless electrical repairs, often on critical circuits. That car has less than 1/5 the wires in it that newer vehicles have.

I have also heard the same story from every one of my mechanics, and several forums.
 

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From Green Car Congress on Honda's second generation iMMD system in the 2017 Accord HEV. The first generation was in the 2014 Accrod PHEV, and the third is in the 2018+ Accord, 2019+ Insight and Clarity, and 2020 CR-V.
  • Electric servo brake system. The Accord Hybrid’s electric servo brake system maximizes regenerative braking capability for improved fuel efficiency. The braking system is fully hydraulic from the master cylinder all the way to the 4-wheel disc brakes, just like a traditional braking system. The key difference is that the braking function is electronically controlled rather than a purely mechanical activation, allowing regenerative braking from the electric drive motor to slow the vehicle, rather than the hydraulic friction brakes under most circumstances. Besides its payoff in efficiency, the system offers excellent feel and feedback for the driver through the brake pedal.
  • When the driver applies the brake pedal, a signal is sent to the vehicle’s Electronic Control Unit (ECU), which determines the appropriate amount of braking force to assign to regenerative braking through the electric drive motor and to the hydraulic friction braking system. In many cases, friction braking is not needed until the vehicle speed drops below 5 mph, as the vehicle slows to a final stop.
  • When the ECU determines that friction braking is needed, the dual hydraulic master cylinder pumps brake fluid through the system. Midway between the master cylinder and the calipers is a separate motorized electronic actuator. This actuator receives an electronic signal, generated in the master cylinder module that precisely defines how the driver has applied the brakes – soft or hard, slow or fast. The actuator then directly apportions hydraulic pressure to the brake calipers at each wheel.
  • While the gasoline Accord uses a 10-inch vacuum booster to assist the driver in applying needed brake pressure, the Accord Hybrid uses an electric servo brake actuator. The vented front brake rotors are 11.5 inches in diameter, while the rear discs are 11.1 inches. Both front and rear calipers have one piston each.
  • For 2017, the initial force required to activate the braking system has been lowered by approximately 10% for further improved, more linear brake control. Together with a smaller, lighter design, a finer control logic allowing a 25% increase in maximum regenerative brake torque combine to further improve fuel efficiency.
 
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From Honda Technical paper Development of Electro Servo Brake System:
  • The system employs a configuration in which the pedal input is transmitted directly to the master cylinder ... when the servo is not in use, for example when the system is shut down.
So there is a direct connection, but the servo system interrupts it when in use. This is what it can do when in use:
139893
 

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Please provide documented proof of this claim.
...
To JB is AZ, I now have my second car past 200k miles, and one past 400k miles. I have only ever seen mechanical controls break twice, and they were for secondary systems that the car does not need to operate. My 400k car is still sitting in my driveway at 39 years old, 100% of its mechanical controls still work, but that car has needed countless electrical repairs, often on critical circuits. That car has less than 1/5 the wires in it that newer vehicles have.

I have also heard the same story from every one of my mechanics, and several forums.
OK....First, let me apologize for my request that you provide documented proof of your claim. Obviously, you own personal experience is not "documented proof".

With that said, I have no interest in debating this issue with you.

We are on complete opposite sides of car ownership plans. I have no desire to own a car at or even near 100,000 miles, or beyond 4 or 5 years of age. I enjoy the new tech and safety features new cars provide, and the advancement in ride, noise levels, comfort, fuel economy, etc.

My brother in law has a 2005 Pilot with somewhere around 220,000 miles, most likely, way more than that by now, as we haven't seen them in a few months due to the virus. Besides the inconvenience of frequently taking it in for repairs, and the times it has left him without a vehicle, it has also cost him THOUSANDS of dollars in repairs, and the leather on the seats have totally cracked and deteriorated, so for several years, he has poor fitting seat covers that frequently slide around and basically just look awful. He has no children and no pets. He now grudgingly admits that for the amount of money he has spent on repairs, he could have paid for a new car...at least once during the time he has owned his Pilot. He recently set off to drive from Southern AZ to Southern Cal, and the A/C quit half way there....in the summer!....He drove the rest of the way there, and back, with 3 adult passengers, without A/C. When he got back to AZ, the repair cost was over $2,000. Yeah. He keeps saying, "I have replaced everything, there is nothing else to repair." NOT!

I never want to own a car that I wonder, even in the back of my mind, when I set off on a drive, short or long, that I will have a part fail or need to call a tow truck, and then spend a lot of money repairing it.

I apologize to all, as this is WAY off topic.

END
 

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We are on complete opposite sides of car ownership plans. I have no desire to own a car at or even near 100,000 miles, or beyond 4 or 5 years of age. I enjoy the new tech and safety features new cars provide, and the advancement in ride, noise levels, comfort, fuel economy, etc.


END
I am on the opposite side from you as well. Every car I buy will be at least 5 years old, preferably 8 to 10 years old. However, I always have at least two cars. This makes keeping up on maintenance easier. I have read on forums about common problems with different models of cars that are still under warranty. Dealer responsiveness varied greatly depending on location. The thing with a used car, is that those problems, have generally been fixed by the time I buy them. I will then be looking at general wear and tear, and routine maintenance. I am not a mechanic, but I know enough to bring my vehicles in for servicing BEFORE something actually fails. Lack of routine maintenance is a common reason for "unexpected" mechanical failures. Aside from keeping up on routine maintenance I also have a reader attached to my OBD port, so I can monitor in real time, battery voltage, engine temperature, etc. I have only had one car break down on me on the side of the road, and that was many years ago, when I wasn't as attentive as I am now.

I don't know the price of a new car comparable to what your brother in law has, but it has been my experience, that I would have to replace the engine in my car every year for 6 or more years, before it would cost me as much as a new car. I no longer have my CRV, but of my other 3 cars, there is no way the maintenance cost would be enough to buy even one of my cars outright. The combined purchase price of my 3 cars was $27,000. The price new, if bought in the year they were produced, would have been $170,000. The price of those cars if bought new in the same year I bought them used would have been $202,000. Except for the car I call my "hooptie"(a Nissan), all of my cars have a great ride, noise level and comfort. They do lack in the fuel economy category. However, if I cared about fuel economy I wouldn't have bought V-8s. If anything, I regret not buying the supercharged model of MY 2012 Jaguar XJL. The NA-V8 engine is good, but my previous Jaguar XF was supercharged V-8, and it was absolutely EXHILARATING. Plus the supercharged models always come with adaptive cruise control and blind spot indicator(which I don't have on my XJL).
 
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