# Is it me getting used to Regen braking or … they are somewhat getting soft? - (Fun Chart)



## r-e-l (Dec 19, 2018)

ok, let me start with a fun picture that shows how Tesla changed my driving. The picture below was taken out of an app called EverDrive.
I installed it way before I had a Tesla. The goal of the app is to measure how you drive. I installed it on my phone and my daughter who just got a her license to do a fun competition on who drives safer.
The app measure rapid acceleration, hard breaks, cornering, speed, phone use ...

I was doing 'ok' till I got the Tesla early Dec and then … 

Ok, acceleration score going down is expected... I got to try it out and do all the demos. 
Breaking on the other hand … wasn't me doing hard breaks but a result of the regenerating breaks getting into action. Lifting the leg from the "gas" always resulted is fairly fast slow down, enough that clearly it was caught by the app as shown in the chart.
About a week after, I felt the car no longer slows as it used to be to the point I was thinking to take it to service (It also came with all sorts of warning that "regen breaks are limited". I wasn't sure, so I gave my wife to drive the car and she too felt its not the same.
As the chart shows, my score started to go up as well. 
This might be a combination of me getting used to how the car drives but also might be there is an issue.

questions:
Do other folks felt after a week or so of use that the reg breaks have changed on them (they either adjusted automatically or they "break in") or does it feels like "day one"?
Is there a way to see how much the car regen overtime? the energy chart is not detailed enough? 
Anyone took their car for service on this topic and were they able to quickly assess if there is an issue and if it might be related to the "reg limited warning" that is fairly random?


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## iChris93 (Feb 3, 2017)

r-e-l said:


> "regen breaks are limited"


This is likely due to colder weather you've experienced since you first got the car.


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## Bigriver (Jan 26, 2018)

It doesn't sound like anything is wrong with your brakes. Regen is limited when either your battery has a lot of charge (e.g. > 90%) or when it gets colder outside (degrades starting at about 60 F). Regen can return as you continue to drive and the battery heats up. In addition to the message telling you that regen is limited, you can always see your regen status where I have circled on the attached picture. The dashed part indicates reduced regen - mine is reduced just a little bit here. When regen is totally unavailable, it will be dashed all the way to the center, under the P. As you drive, Watch this area and you will be able to see with a green line when regen is occurring. The green line will never move into the dashed region. The green line is only instantaneous info; there is no cumulative/past regen stats. Hope this helps a little.


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## r-e-l (Dec 19, 2018)

The regen comes and go, to the most part its not there. However, the feeling of releasing the "gas" and the car starts to stop that is almost not there. 
it just started around the same time. for past few weeks I hardly saw the error message but again, a week after the car arrived the friction you feel when releasing the gas and the car starts to stop is missing. 
Its not completely gone but feel drastically different.


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## iChris93 (Feb 3, 2017)

r-e-l said:


> The regen comes and go, to the most part its not there. However, the feeling of releasing the "gas" and the car starts to stop that is almost not there.
> it just started around the same time. for past few weeks I hardly saw the error message but again, a week after the car arrived the friction you feel when releasing the gas and the car starts to stop is missing.
> Its not completely gone but feel drastically different.


Is your car RWD? Did you put winter tires on?


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## Bigriver (Jan 26, 2018)

r-e-l said:


> The regen comes and go, to the most part its not there. However, the feeling of releasing the "gas" and the car starts to stop that is almost not there..... hardly saw the error message


So the "regen" comes and goes, but the slowing of the car when releasing the accelerator is rarely happening? I'm a bit confused because these 2 things are pretty much synonymous.

You also referred to the Regen is Limited warning as an error message. I would note that it is a message that all of us see in cold weather, and isn't an "error" but is a notification about the state of the battery. This message does not appear for just a little bit of regen disabled, but does appear when a notable percentage is disabled. A cold battery can be limited in the rate it can charge, and can likewise be limited in the amount of energy it can receive from regen.

There is also a car setting to set regenerative braking to either standard or low. You might want to check whether that has inadvertently gotten changed.

@iChris93 does point out a valid possibility -- there has been a problem noted by many for RWD with winter tires. Check out the "Who has lost regen with winter tires?" thread. That is strictly linked to RWD and is not applicable to AWD.


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## r-e-l (Dec 19, 2018)

@Bigriver - I am saying its error for two reasons:
1) its not that cold - 54. 
2) lets assume 54 is cold. The fact I stop the car when it happen. put on park. open the door, close the door and start again and the message goes out makes me feel its random.

But lets assume its accurate. Most of the time, I don't see the message on the screen. However, that initial feeling the car slows down once releasing the accelerator is almost gone. Its nothing like what it was when I first got it.

I was showing the chart above to show how soon the app registered me slowing down the first week after getting the car and how its getting more and more normal (like normal) cars.
It can either be because I somehow got used to it or … something have changed and it is indeed using less resistance.

hope this makes more sense.

btw: yes, this is a RWD - the tires … what ever comes by default.


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## Bigriver (Jan 26, 2018)

@r-e-l, I agree that the regen is limited message can be fleeting. I don't know exactly when it is displayed and not. I would suggest to perhaps pay more attention to the dashed line, as it provides real-time info that is needed to adjust response based on the amount of regen that is available.

For me, I believe that my initial time driving a Tesla created more abrupt stopping. Honestly, I drove like a jerky 16 year old new driver for awhile, getting used to what is largely 1-pedal driving. Now I keep my foot on the accelerator longer, and I think my deceleration is much more ICE-like (even as I get the benefit of regen.)

In your plots, I don't understand the x-axis for the bottom 3 - if they are the same as the top graph then you haven't shown any data after early December when you got the car. But I am presuming the x-axis is different than the top one, and that the clearest indication of the timing that you got the Tesla corresponds to the change in your acceleration grade. Yes, there is a change in your braking at that time, but your braking grade had quite a bit of variability even before that. So seems there are a lot of factors and different conditions going into that, and it's not showing to me any clear change.

Obviously if you feel there is a problem you should contact service. I would suggest, though, that you are able to identify specific days and times that you thought something was wrong. They usually ask for that info. They can look back in the car logs and see what was going on.


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## MelindaV (Apr 2, 2016)

Bigriver said:


> I would suggest, though, that you are able to identify specific days and times that you thought something was wrong. They usually ask for that info.


in tracking an odd issue with my car, I've been taking a pix of the screen when it happens, so I have an exact time/date (from the phone's photo info) of when it happened. My service guys have mentioned this is more helpful to them in tracking an issue than looking for prior Bug Reports recorded from your car.
(if apple ever looks at photos/albums made I am sure they would be thinking "is taking a pix of the car screen the new taking a pix of your lunch?")


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## r-e-l (Dec 19, 2018)

Tesla did contact me and are asking me to file bug report on the fly - I didn't know it but when filing the bug from the car, they capture whats is showing up on the screen. 
This might help diagnose the regen message but doubt it can help with what I think you call "ICE" (what does it stands for? known term to Tesla engineers?)


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## Bigriver (Jan 26, 2018)

ICE = internal combustion engine. I used it in context of just referring to non-electric “normal” (for most of the world, for now) cars and how they respond.


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