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Discussion Starter #1
Hello folks,

I noticed a strange thing today. Driving in 'L', I had stopped at a red light. Suddenly I heard the familiar sound of the Parking Brake engaging itself. This was very odd because I did not activate it. My hands were on the steering wheel. I pushed down the brake switch and it disengaged. Wonder if anyone has had this problem. My bolt is just about a week old. Love it, otherwise.

Cheers,
Jit
 

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Did you have your foot off the brake pedal while at the light and were you on a hill?
Did you have your seat belt on?
 

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Hi,

I live on a hill and my driveway is on a grade and have noticed a few things which may put you at ease.
When I don't pull into my garage and park in my driveway, I notice that the parking brake engages and I have to physically push the acceleration pedal and it releases the parking brake.
The car kind of lurches out of 'parking brake mode' and I have noticed similar things happening when stopped at a light on a grade while traveling uphill.
The parking brake does make a very noticeable sound if you are moving and the parking brake is engaged, it is alarming when you first hear it but I believe it is completely normal.
 

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The car is "smart" enough to not let you drive with the parking brake on. So if you are parked and hit the accelerator (forward or reverse) it will disengage the parking brake for you. However you should not accelerate quickly while it is doing that as you can damage or just reduce the life of the parking brake, it still is a physical brake being engaged.

I have had my car put mine on for me when I am on a hill before, does it in my drive way sometimes as well. I wouldn't be concerned with it unless it is doing it more on level ground.
 

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It makes a ridiculous clatter if you engage the parking brake while moving. I wouldn?t recommend it, it sounds like things breaking.
 

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It makes a ridiculous clatter if you engage the parking brake while moving. I wouldn?t recommend it, it sounds like things breaking.
I would bet it does, i'm actually surprised it lets you engage it while in motion. Unless I have something set and don't realize it mine will disengage for me if I even touch the accelerator while not moving and the parking brake is engaged. I've just assumed that was default behavior.
 

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I think it is more than just a physical brake in the traditional sense. It also has some sort of pawl that locks the motor and that's probably what makes the unusual sounds.
I don't think that is the case, putting the car in park locks the motor, not putting the parking brake on. The parking brake in the Bolt only makes all those noises because there are electronic motors setting/unsetting the brake.

Parts list for the parking brake on the Bolt are just around the actual brake assembly and then the actuator, which is what makes the noise when it operates.

https://www.gmpartscenter.net/auto-parts/2017/chevrolet/bolt-ev/premier-trim/electric-engine/brakes-cat/parking-brake-scat
 

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Discussion Starter #9
I was on level ground and I can't remember where my foot was unfortunately. Be default, I would keep it on the brake pedal.
 

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Discussion Starter #10
Hi,

I live on a hill and my driveway is on a grade and have noticed a few things which may put you at ease.
When I don't pull into my garage and park in my driveway, I notice that the parking brake engages and I have to physically push the acceleration pedal and it releases the parking brake.
The car kind of lurches out of 'parking brake mode' and I have noticed similar things happening when stopped at a light on a grade while traveling uphill.
The parking brake does make a very noticeable sound if you are moving and the parking brake is engaged, it is alarming when you first hear it but I believe it is completely normal.
Thanks for the reply. I think that is what happened. It released when I pressed the accelerator pedal. I'm not sure if I pushed on the Park Brake button as it took me by surprise and traffic had begun to move.
 

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I don't think that is the case, putting the car in park locks the motor, not putting the parking brake on. The parking brake in the Bolt only makes all those noises because there are electronic motors setting/unsetting the brake.

Parts list for the parking brake on the Bolt are just around the actual brake assembly and then the actuator, which is what makes the noise when it operates.

https://www.gmpartscenter.net/auto-parts/2017/chevrolet/bolt-ev/premier-trim/electric-engine/brakes-cat/parking-brake-scat
I confused the two. I thought putting it in Park engaged the Parking Brake but I now recall the story of the guy trying to tow the Bolt behind an RV with the front wheels off the ground. Lifting the front took car of the pawl locking the motor which locks the front wheels as soon as you shut off the Bolt but the Bolt would automatically engage the parking brake after a bit and that locked up the Bolt's rear wheels and he wore off the rear tires from dragging them. His solution was to disconnect the 12V battery before the parking brake engaged.
 

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I confused the two. I thought putting it in Park engaged the Parking Brake but I now recall the story of the guy trying to tow the Bolt behind an RV with the front wheels off the ground. Lifting the front took car of the pawl locking the motor which locks the front wheels as soon as you shut off the Bolt but the Bolt would automatically engage the parking brake after a bit and that locked up the Bolt's rear wheels and he wore off the rear tires from dragging them. His solution was to disconnect the 12V battery before the parking brake engaged.
Oh that sounds fun, dragging rubber, heh.
 

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It makes a ridiculous clatter if you engage the parking brake while moving. I wouldn?t recommend it, it sounds like things breaking.
I would bet it does, i'm actually surprised it lets you engage it while in motion. Unless I have something set and don't realize it mine will disengage for me if I even touch the accelerator while not moving and the parking brake is engaged. I've just assumed that was default behavior.
The brake does disengage if I push the accelerator, as designed. But if you accidentally engage the brake while you?re moving, it makes a lot of noise. I?m also surprised that it?s even possible, it seems like something that software should lock out.
 

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The brake does disengage if I push the accelerator, as designed. But if you accidentally engage the brake while you?re moving, it makes a lot of noise. I?m also surprised that it?s even possible, it seems like something that software should lock out.
Yeah, that was my first thought as well, the car just should not allow you to engage the parking brake while moving. However, then I thought about why would you ever use the parking brake in any car while in motion. Made me realize it could still have a safety usage, as in for some reason normal and regen brakes fail so you need to do something to slow down, parking brake would be the only option left. So my guess is they still want that to be an option and with the button placement it would be rather difficult to engage it on accident.
 

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I have also had this occur. See in the owner's manual under "Driving and Operating => Electric Drive Unit => One-Pedal Driving" where it describes that the parking brake may engage "if the vehicle cannot maintain the grade" (and you presumably do not use the brake ... ergo one-pedal driving). I was able to reproduce the behavior and now feel confident that it is a feature and not a bug.
 

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I would suggest always using the brakes to hold the car on a hill. The hill hold function uses battery power through the motor, and I can't imagine the motor is very efficient at zero rpm. Stepping on the brake does not.
 

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I would suggest always using the brakes to hold the car on a hill. The hill hold function uses battery power through the motor, and I can't imagine the motor is very efficient at zero rpm. Stepping on the brake does not.
Plus, it puts your brake lights on - a safety issue!
 

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Although interesting to note that the brake lights are activated when "one-pedal driving" (i.e., using "L" without brake pedal) when computer thinks you would otherwise be applying the brakes.
When decelerating, whether "D", "L", regen paddle, or brake pedal, the brake lights come on. When you come to a complete stop, they go off UNLESS you are applying the brake pedal.
 

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When decelerating, whether "D", "L", regen paddle, or brake pedal, the brake lights come on. When you come to a complete stop, they go off UNLESS you are applying the brake pedal.
Regen braking in D, that is just letting off the accelerator (unless using the paddle) does not trigger the brake lights. It is supposed to simulating letting off the gas in an automatic.

Also saying all deceleration triggers the brake lights is slightly incorrect as well. With L the deceleration force has to be .1g or higher, so if you only slightly let off the accelerator it won't trigger the brake lights.

If you said the regen paddle always triggers the brake lights you would be correct, my understanding of that is anytime you use the regen paddle while in motion the brake lights are triggered.
 
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