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Discussion Starter #1 (Edited)
A few days ago I noticed that my "L" mode wasn't slowing the car down hardly at all. In fact, even at a dead stop, the car kept on trying to go forward when my foot was off the brake. At first I thought it was due to my recent charging of the Bolt. Well, now it's below 50% and still doing the same thing. It's almost as if "L" mode is like "D" mode.

The "flipper" on the wheel, used for add'l regen, is maybe 20% of what it once was, in regard bringing the Bolt to a stop. Not only that, but from a dead stop, with the flipper held to the rear, the car moves forward.

I've scheduled a service visit for Thur, Sept 26th (earliest date they could get me in), but was wondering if anyone on this forum knows some "magic" that I can perform to bring my regen back to the way it was?

Thank,

Rich
2019 Premier, 4,000 miles on the odometer
 

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I'm guessing that the issue did not go away even after cycling the power (i.e. turning it off, then on again)?

Up to the 2018 model, the L mode would function like D if the seat belt was not buckled, or if the driver side door was open. Due to this, errors with the door / belt sensor occasionally caused the L-works-like-D bug. But since you have a 2019 model, which does not follow this logic, the problem may lie somewhere else.
 

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Discussion Starter #3
Yeah, I read all the previous threads on this issue prior to this posting. It's not a deliberately unbuckled belt, and my car is a 2019 anyway.

I suspect a relatively minor computer bug. We'll see in a little over a week. Meanwhile, back to the use of brakes!! Darn.

Rich
 

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It's definitely not behaving as it should. When you move the shift lever down to go from D to L, I assume L illuminates on the shifter and L also appears (lower right) on the display behind the steering wheel? I don't even know if it's possible for the two (shifter and display) to disagree but I'm just thinking that something somewhere isn't registering the L selection.

Mike
 

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Are you saying that in general L mode doesn't stop the car, or just that once stopped the car doesn't always stay stopped but can creep forward?

If it's the latter, yes, that's a feature. Sometimes based on terrain (i.e., slope) and phase of the moon, the car won't be able to hold itself perfectly still.
 

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Discussion Starter #6
Are you saying that in general L mode doesn't stop the car, or just that once stopped the car doesn't always stay stopped but can creep forward?

If it's the latter, yes, that's a feature. Sometimes based on terrain (i.e., slope) and phase of the moon, the car won't be able to hold itself perfectly still.
Vertiformed, I have 4,000 miles on my Bolt. Only ever driven in "L" mode. The car has never moved from a stop, on a level surface, until a few days ago, when in L. It moves forward with a good deal of speed, perhaps three or four miles an hour (rough estimate). The flipper is far less efficient in stopping the car when pressed. Even with the flipper pressed, the car moves forward from a stop.

Clearly something is wrong, and it's not operator error.

The Bolt will be going into the dealer on the 26th. I hope it's simply a computer glitch of some sort. The Bolt is operationally fine, except for this annoyance. And that is what this is, not an existential, life-ending problem, just a matter that ought to be looked at and remedied at the dealership.

Rich
 

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Vertiformed, I have 4,000 miles on my Bolt. Only ever driven in "L" mode. The car has never moved from a stop, on a level surface, until a few days ago, when in L. It moves forward with a good deal of speed, perhaps three or four miles an hour (rough estimate). The flipper is far less efficient in stopping the car when pressed. Even with the flipper pressed, the car moves forward from a stop.

Clearly something is wrong, and it's not operator error.

The Bolt will be going into the dealer on the 26th. I hope it's simply a computer glitch of some sort. The Bolt is operationally fine, except for this annoyance. And that is what this is, not an existential, life-ending problem, just a matter that ought to be looked at and remedied at the dealership.

Rich
My 2019 Bolt has almost 16K miles on it. There have been times where I'm in L mode and I engage the paddle and the car never comes to a complete stop, it still creeps forward at a 1/2MPH or so. It has happened a dozen times in the 10 months I've owned the car. I have not found it to be terrain specific, it happened today and it was relatively flat. I drove about 100 miles today, all city driving, zero highway. All of it in 'L'
 

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Discussion Starter #8
Zoom, as I mentioned, after taking the Bolt to the dealer for them to look at the car, I'll report back on what they find. Again, this is not a "major" issue, just a relatively minor annoyance.

I enjoyed both the virtually complete one-pedal braking of L-mode, as well as the car not creeping forward after coming to a complete stop. Hope to get that back.

Rich
 

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My 2019 Bolt has almost 16K miles on it. There have been times where I'm in L mode and I engage the paddle and the car never comes to a complete stop, it still creeps forward at a 1/2MPH or so. It has happened a dozen times in the 10 months I've owned the car. I have not found it to be terrain specific, it happened today and it was relatively flat. I drove about 100 miles today, all city driving, zero highway. All of it in 'L'
IMO if people are having that problem, I wouldn't just accept it. I only have 1000 miles on my 2019 but it has never failed to remain stopped in L, even on hills (both up and downhill). I would take mine in right away if it did that because if there's no one behind me (so I don't need the brake lights), I depend on L sitting still and might have become complacent over time, assuming the car won't roll in L. Now that I've seen this thread, I'll have to be more careful. Or just rest my foot on the brake every time now, even when there's no one else around. I don't want to assume the car won't move and end up rolling and not realizing it.

I don't know how it works in the Bolt but on my RC cars, what amounts to a big resistor is used to apply the brakes when stopped: if you "short out" a motor, it resists turning. What if whatever they use to apply a resistance to the motor is worn out or has a defect?

Mike
 

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A few days ago I noticed that my "L" mode wasn't slowing the car down hardly at all. In fact, even at a dead stop, the car kept on trying to go forward when my foot was off the brake.
Note that the car will "creep" in "L" mode if you don't have the driver's seat belt fastened. If your seat belt is indeed fastened, a problem with the "seatbelt fastened" sensor could also cause the car to creep, but you'd think that if this was the case then there would be other obvious symptoms, such as the car chiming at you all the time.
 

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IMO if people are having that problem, I wouldn't just accept it.

I don't know how it works in the Bolt but on my RC cars, what amounts to a big resistor is used to apply the brakes when stopped: if you "short out" a motor, it resists turning. What if whatever they use to apply a resistance to the motor is worn out or has a defect?

Mike
Our 2017 has never done this. I would definitely be notifying the dealer, and GM, if necessary.

As to the regen...this is not a brushed DC motor, and they are not shorting the motor to brake. It is waaaay more sophisticated than that.
 

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Rich sorry to hear this. :cry:
Maybe it's an omen that it is about time for you to come back to Arizona. :eek:
We now have about 11K miles on our 2019 without any problem like this. On an incline it will sometimes roll a little. But on level roads it always stays put. ❗
 

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Rich sorry to hear this. :cry:
Maybe it's an omen that it is about time for you to come back to Arizona. :eek:
We now have about 11K miles on our 2019 without any problem like this. On an incline it will sometimes roll a little. But on level roads it always stays put. ❗
On an incline it will creep so slowly that you may not even notice. Something to be aware of especially in stop and go traffic. You may roll into another car if stopped long enough.
 

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On an incline it will creep so slowly that you may not even notice. Something to be aware of especially in stop and go traffic. You may roll into another car if stopped long enough.
my automatic parking brake stops mine if the car can't handle the incline. usually put my foot on the brake to prevent the parking brake from actuating.
 

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Our 2017 has never done this. I would definitely be notifying the dealer, and GM, if necessary.

As to the regen...this is not a brushed DC motor, and they are not shorting the motor to brake. It is waaaay more sophisticated than that.
I'm sure, but at it's simplest level, they must be using the same basic idea. The "shorting" method works on permanent magnet DC motors. On AC induction motors, you can do it by injecting a DC current to get the same effect.

Mike
 

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IMO if people are having that problem, I wouldn't just accept it. I only have 1000 miles on my 2019 but it has never failed to remain stopped in L, even on hills (both up and downhill). I would take mine in right away if it did that because if there's no one behind me (so I don't need the brake lights), I depend on L sitting still and might have become complacent over time, assuming the car won't roll in L. Now that I've seen this thread, I'll have to be more careful. Or just rest my foot on the brake every time now, even when there's no one else around. I don't want to assume the car won't move and end up rolling and not realizing it.

I don't know how it works in the Bolt but on my RC cars, what amounts to a big resistor is used to apply the brakes when stopped: if you "short out" a motor, it resists turning. What if whatever they use to apply a resistance to the motor is worn out or has a defect?

Mike
When the service side of this industry gets better, because it is far from it now, I would consider taking it in for a problem that is this intermittent. Microsoft Windows has taught me to accept a lot of things that just shouldn't be. I would rather have them fix the backup camera guide line issue that many of us have reported here. There are times where I reverse, and I have no guidelines. Do I really need them, no. But that irritates me......pressing the brake for whatever reason does not. Just my thoughts.
 

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My creeping in L while holding the paddle engaged is very intermittent, and the speed is by my best estimate less than 1 MPH.
 

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Rich, I started having this same problem this past Friday (09/20/19) and I'm very curious what the service department says. I have 11k miles on my 2019 and have always driven in L mode. In my situation, I actually heard a slight pop, then the regen had a spongy feel to it while engaging and slowing the car to a stop that one time. Since then, my regen has far less bite to it when slowing the car down.
 
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