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I have been reading the forum for awhile so I'm disappointed this is the reason for my first post.

I have had my bolt for almost 2 month now. It's been good. Mostly using the L mode since I still drive another car sometimes and do not wanna to confuse myself with paddle braking versus traditional brake pedal.

On this rainy morning while turning to park in a stall and so I take my food off the accelerator and expected the heavy regenerative braking. Instead it accelerated in to the stall and so I had to brake heavily and it still didn't seem to take hold. Luckily the cement parking block stopped the car albeit I still went over it. No damage but adrenaline.

Anyone else have this problem? I'm pretty confident I was in L and it responded as expected a few seconds earlier when I entered the lot. Did the rain cause the regenerative braking to fail and I should avoid it during the oddly rainy season here? I know first gen of a new car can have some kinks but I'm don't want to end up with kinks myself.
 

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Very possible for Regen to deactivate in slippery conditions. Hitting a large bump may also disengage Regen, which will feel like the car is actually speeding up (since you are expecting it to decelerate)
Most likely this ^

I have experienced this, as I guess many have, with the Volt too in slippery conditions. Need to have that foot over the brake too when coming to a stop, ready to step on it, especially in wet conditions.
 

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I think we are starting to see the problem with "one pedal driving". There are too many conditions where it may not be available, yet the user gets used to it and starts to depend on it. It's there until it isn't. It might be a good practice to use the good ol' fashion brake pedal for full stops. It's only a matter of time before somebody rear ends somebody else, or sails into an intersection when this feature cuts out due to a full battery, or something else.
 

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Sounds like a similar experience that Leaf drivers have complained about on mynissanleaf.com. When braking on uneven or slippery pavement regenerative braking can suddenly deactivate and instantaneously switch to total friction braking. For a moment it "feels" like the brakes fail and the car accelerates. But as your foot is already on the brake pedal you just push harder and the car stops. Always a very memorable experience for the driver. I have watched this Forum to see if drivers would have a similar experience while one pedal driving in the Bolt. Bolt drivers really need to be made aware of this so that they can adjust before experiencing it firsthand.
 

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The Volt behaves likewise. Hit some broken pavement with poor traction, and regen goes away. It feels like it accelerates, you slam on the friction brakes, and your heart races.

This is why I and other more cautious Volt owners, suggest never using L in low traction conditions. I avoid it in snow and ice completely, as I want all 4 wheels working together to slow me in a controlled manner using ABS if necessary. Before the tail swings out.

Others feel this is way too cautious. To each his own I suppose.

Now in rain, I'm usually not against using L. I assume you weren't traveling more than 10 mph in the parking lot? I am surprised that at such a low speed, L had enough stopping power to break traction and shutoff regen. I'm wondering if something else happened.
 

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I think we are starting to see the problem with "one pedal driving". There are too many conditions where it may not be available, yet the user gets used to it and starts to depend on it. It's there until it isn't. It might be a good practice to use the good ol' fashion brake pedal for full stops. It's only a matter of time before somebody rear ends somebody else, or sails into an intersection when this feature cuts out due to a full battery, or something else.
I completely agree. I use L in traffic, but I also use the brake pedal when stopping or stopped. L is too uncontrolled for entertaining driving, and regen only works on the front wheels.
Also, if you ever plan to drive an ICE car again, and your reflexes expect it to stop when you lift off the accelerator, you will be in deep trouble...
 

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So does anyone know the answer to this question please? Do I get the same amount of regenerative braking from D and the brake pedal in normal driving as I get from L in normal driving? If the answer is yes then L just spares me the effort of lifting my foot from the accelerator pedal to the brake, but at the risk of having my foot on the wrong pedal. Thanks
 

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So does anyone know the answer to this question please? Do I get the same amount of regenerative braking from D and the brake pedal in normal driving as I get from L in normal driving? If the answer is yes then L just spares me the effort of lifting my foot from the accelerator pedal to the brake, but at the risk of having my foot on the wrong pedal. Thanks
That is a great question and something I have been thinking about. My guess is no. It feels to me like the regen while braking is very limited. My guess if you watch the power flow on the dash with braking it never goes to as many kW as the regen, which can run up to about 30 or 40 kW on occasions. Just don't run into anything while doing the tests! I like to use drive and regen, but definitely need to have my foot on the brake and pay attention, since the regen is not all that predictable. Also, the regen is either on or off and is not variable like braking pressure.
 

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When I was driving the Bolt today I still was covering the brake peddle even though I didn't use it. A good habit but I wonder if I will keep it the more I drive a Bolt. This post tells me I should!!
 

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Do I get the same amount of regenerative braking from D and the brake pedal in normal driving as I get from L in normal driving?
Yes, as long as your deceleration is a gentle as your Regen setting (paddle or not). The friction brakes do waste energy, but only when you brake hard enough to engage them.
The brakes also work on all four wheels, instead of only two, making the car more stable in slippery conditions.
 

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On this rainy morning while turning to park in a stall and so I take my food off the accelerator and expected the heavy regenerative braking. Instead it accelerated in to the stall and so I had to brake heavily and it still didn't seem to take hold.
A problem with regenerative braking is that the friction brakes stay cold, wet, and dusty. Friction brakes are surely going to be a dissapointment if you need them urgently under those conditions. Always a good habit to safely do little maneuvers that will keep them warm and dry. Of course that applies to any car, but especially important for one with a lot of regenerative braking. I try to be sure to use the brake pedal for the first stop of the drive and then from time to time.
 

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Yes, as long as your deceleration is a gentle as your Regen setting (paddle or not). The friction brakes do waste energy, but only when you brake hard enough to engage them.
The brakes also work on all four wheels, instead of only two, making the car more stable in slippery conditions.
And this brings up another interesting thought. I'm assuming that the transaxle in the Bolt is open and not limited slip. I kind of figure that during regenerative braking, it works in reverse. This means at some point, one wheel is doing all the braking and the other is freewheeling on a slippery surface. I might be very wrong about this. I wish I knew what goes on.
 

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Very possible for Regen to deactivate in slippery conditions. Hitting a large bump may also disengage Regen, which will feel like the car is actually speeding up (since you are expecting it to decelerate)
I dunno about this. It seems unlikely to be the cause based on my experience.

I've driven probably close to a thousand (of my total approaching 3,000) miles in rainy, slippery conditions, including the recent deluges in California, in which I drove through puddles a foot deep. Never once did I see regen disengage, and I pretty much always drive in L. I've driven on wet highways, wet local streets, wet parking lots, my own expoxy garage floor while wet. Never lost regen. Would it really happen at parking speeds, while pulling into a space? At what, 5 or 10 mph? I guess anything's possible, but it seems highly unlikely.:confused:

The only times I've been surprised by missing regen is when my seatbelt was unfastened. GM kills regen deliberately in this situation. Boltface, any chance you had unbuckled your seatbelt in anticipation of parking?

(I understand a near-full battery also prevents regen, but it doesn't sound like that's what happened here.)
 

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I've seen this happen several times in my old Honda Civic Hybrid as well as in the Bolt (just once). The regen seems to disengage when the car experiences a sudden jarring motion. It was most noticeable my old car when I was exiting a freeway and hit a pothole or bump on the off ramp. In the old car, I read that this was to prevent damage to the regen system. I'm guessing that it is the same with the Bolt.
 

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Discussion Starter #16
I absolutely agree with everyone here that you should still cover the brake and that was the case here. I was absolutely mashing the brake in this case.

However, in most cases the car pretty much stops as soon as you release the accelerator.

There was a discussion with the Chevy rep we know who also bought the same car. He mention that at low speeds the reg braking can stop and you will coast. We were able to reproduce this in another lot. I would expect that UI/UX here needs a it of polish to guide users when it is and isn't active.



That is a great question and something I have been thinking about. My guess is no. It feels to me like the regen while braking is very limited. My guess if you watch the power flow on the dash with braking it never goes to as many kW as the regen, which can run up to about 30 or 40 kW on occasions. Just don't run into anything while doing the tests! I like to use drive and regen, but definitely need to have my foot on the brake and pay attention, since the regen is not all that predictable. Also, the regen is either on or off and is not variable like braking pressure.
 

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Not if one has the sense to not rest on the brake pedal, and it can give the benefits of both one- and two-pedal driving: immediate access to full braking with all four wheels...
 

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There was a discussion with the Chevy rep we know who also bought the same car. He mention that at low speeds the reg braking can stop and you will coast. We were able to reproduce this in another lot. I would expect that UI/UX here needs a it of polish to guide users when it is and isn't active.
What were the steps you took to reproduce this? Surely it must be more than just moving at low speed.

Better than UI polish would be if Chevy just prevented the one-pedal driving from cutting out unexpectedly. I can't imagine why they would disable it at low speeds, or in any other situation where its not absolutely necessary to disable it (such as full battery or unavoidable mechanical failure). Seems like a recipe for trouble.
 
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