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Discussion Starter #1
Greetings all,

My first post, and I am still shopping for my Bolt EV in the wilds of suburban Philadelphia. I have been driving a Nissan LEAF 'S' since May 2014...so I am old hand in the EV department, and ready to return my lease after 30k electric miles.

I have concluded that the Bolt is a superior vehicle and a better value for my use cases than the vaunted 2018 Nissan LEAF (which I have sat in, but not yet driven).

A simple enough question....the Bolt brakes. I took a test drive yesterday, and the Bolt LT was nice enough, but the brakes seemed problematic. In that every time I stopped, the deceleration seemed normal enough until my speed dropped to almost zero, and then instead of jerking to a stop, the Bolt creeped another foot or two before stopping. Enough to poke me uncomfortably forward into traffic. :eek:

I thought perhaps the brakes needed a firmer foot, so at the next stop, as my speed got to nearly zero, I stomped hard on the brakes...and still the Bolt ooched awkwardly a foot or two forward after I stomped.

Very disconcerting, and probably a deal killer for the spouse.

I have perused a good chunk of the forum over the last couple days, and heard nary a mention of this effect or the blended brakes in general.

Is my tester a weird lemon....or do other people just all deal happily with oddly squishy (and seemingly unsafe) brakes?
 

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Sounds odd. To be truthful, I've never stopped my Bolt with brakes in D mode. Actually, seldom ever use the brakes at all. Let the car stop in L mode and then only apply the brake to get the brake lights to come on. So having hardly used the brakes in ten days of ownership, I can't say I've ever experienced what you are describing.

edit: the D mode is supposed to give you a automatic transmission feel with a creep forward feature. Not sure if that's what is going on. Seems like it should not creep forward if you're pushing on the brake though.
 

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Greetings all ...

Very disconcerting, and probably a deal killer for the spouse.

Is my tester a weird lemon....or do other people just all deal happily with oddly squishy (and seemingly unsafe) brakes?
Well, not had this issue. In fact have to continually keep my spouse from STEALING MY CAR and driving off with it for some trumped up issue about her car.

I do find after I have driven in L mode (high regeneration) for a while, when I then drive in D mode and brake, I sometimes think the brakes have become weak. I'm like a brainless teenager .... the regen braking is so impressive that I come to think it is "normal" and adjust my driving to it, and then find in its absence that normal braking seems weak.

Above may not be directly relevant to your experience. My brakes are excellent, though my brain is not always so. Yesterday was in a rush to get to a dinner party with my Perfect Wife and drove too quickly onto exit ramp and .... brakes scrubbed speed very well, and kept us from some unhappy event, ... and kept uxorious self from comments from the Perfect Wife.
 

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Discussion Starter #4
Yeah. I was driving in 'D' mode the whole time.

My 2013 LEAF doesn't have one pedal driving...they added that in 2014 and called it 'B' mode. My 2013 simulates an ICE automatic transmission to a 'T' re idling, creeping, etc.
 

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See if you can find another Bolt to test drive. Others have reported modules that are faulty that cause strange behavior until said modules are replaced.

edit: in reliability courses I've taken over the years, they had a term called infant mortality. There's always a small percentage of electronics that fail very early. With so many modules on the Bolt, it just is a matter of probability that a few cars will experience an early failure of a single component. The beauty of electronics, is they're usually very easy to replace when serviceable components have connectors.
 

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Discussion Starter #6
The one we're test driving is outfitted like the one we want, but the wrong color. If we pull the trigger, the dealer will try to swap it for another one in the area.
 

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I only drive in L mode unless I am in zero traffic on the highway, than I put it in D. I can honestly say that I have no idea if my brakes even work... I only hit my brakes when I am at a stop and I do this to make sure my brake lights are on.

Your description does seem a bit odd. I would take another test drive in another Bolt and still see if it happens. I would also test drive the Bolt in L mode, since that is how you should be driving the majority of the time.
 

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Mine stops NOW when you apply the brakes. My experience of one is not statistically significant, but neither is yours. Drive another test drive.
 

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better yet. tell the salesperson that it's the wrong color and something is wrong with it. insist that they need to lower the price by $10K if they want to sell it to you. then get the thing fixed under warranty. still drive another one to confirm your suspicion.
 

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Yeah. I was driving in 'D' mode the whole time.

My 2013 LEAF doesn't have one pedal driving...they added that in 2014 and called it 'B' mode. My 2013 simulates an ICE automatic transmission to a 'T' re idling, creeping, etc.

NOT!!!!!!! B mode is nothing like L mode, at all. L mode is for "One Pedal Driving"
You don't need the brake pedal in L mode. Were you wearing your seat belt ?
Was the HVB fully charged....????
 

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Discussion Starter #11
NOT!!!!!!! B mode is nothing like L mode, at all. L mode is for "One Pedal Driving"
You don't need the brake pedal in L mode. Were you wearing your seat belt ?
Was the HVB fully charged....????
I'll trust you on that...B mode is much weaker regen.

I was wearing my seat belt. And I did not notice the SOC, to be honest....you think the braking was due to D mode and SOC > 95% ?
 

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The iBooster used in the Bolt works as follows, to the best of my understanding. A regen profile is loaded into the brake control, from public comments and experience we believe the Bolt operates under light regen at the beginning of the brake stroke. As the stroke continues it quickly switches from electronic braking ('brake by wire') to plain old hydraulic braking. If you are fully depressing it you are using the hydraulics, and in general most of the time are too. I'll try a few experiments, but perhaps the one you drove has a faulty hydraulic braking system (hard to imagine).
 

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Discussion Starter #13 (Edited)
Another quick question....

In my test drive, I was a little disappointed re the acceleration, which seemed weaker than my 4 year old LEAF. This is for both 0-30 and 30-60 if you will.

I now would guess that I had the bolt in 'Normal' mode, rather than 'Sport'. I gather that the 6.5 sec 0-60 time is in 'Sport' only?

In the LEAF, the normal mode is max power, and there is an optional, power-limiting 'Eco' mode that makes it drive all sad like a Prius.

I want the spouse to try 'Sport'.

I will also have her check SOC to test the brake hypothesis that it was in limited regen.

If we buy one, we'll probably run it in hilltop reserve and sport most all the time, unless we are doing a road trip.

Is there some way to keep it from reverting to 'Normal' mode after you restart the car...or do some of you just hit the 'sport' button every time you start?
 

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I wonder if you were actually using the brakes. In D, the car still does light regen with the brake pedal. You have to push pretty hard to get actual disc braking. There's very little power assist on the disc brakes in this car. It requires a pretty good push.
 

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I'll trust you on that...B mode is much weaker regen.

I was wearing my seat belt. And I did not notice the SOC, to be honest....you think the braking was due to D mode and SOC > 95% ?
That's my theory. I wasn't there, so its hard for me to know what was actually happening.
 

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A note about Sport mode: there is no difference between Normal and Sport mode when you floor the accelerator pedal. You get the same amount of power at that point. And all that Sport mode does is remap the accelerator profile so the throttle is more responsive at the top of the travel of the pedal. I.e less initial travel required to push you back in your seat, and less travel required to make changes in speed. Personally I think it’s a gimmick to call it Sport mode...

As to the original complaint about the brakes, the only issue/problem I’ve had with the brakes is when the car is charged to 100%. At 100% charge, there is little to no regen braking available, which makes me feel that the brakes are a little soft, since I have to press harder on them than I normally do when using Hilltop Reserve. Since I now know that the brakes require a bit more firmer press with a full charge, it’s a little less disconcerting than when I first had the car.
 

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Thanks for the link....I'll figure it is just 'wear in'.
The brake pads will need to seat/bed to the rotors. I have never had a problem with new
cars right off the truck. I bet it's due to HVB SOC and regen deactivation :nerd:

Activate hill top reserve and see if it corrects the problem.
 
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