Model S

Regenerative braking is a JOKE (and a DANGER) after software update!

I've tried to get help from Tesla to no avail, so I guess posting it here and hope for an owner uprising is the only thing left. I LOVE my Teslas, but a BIG part of that was how regenerative braking was so good, I almost never needed to use the brake pedal. As of a software update several months ago, the regenerative braking behavior of my model S is DRAMATICALLY reduced ALL OF THE TIME... hot, warm, cold, half charged... it doesn't matter. This is not the same as when it's at or near capacity and can't be charged, and I live in southern California, so unless 60-80 degree weather is considered "cold" then temperature is not a factor either.

I've tried to put up with it thinking Tesla would release a fix immediately because of how dramatically it changed the driving dynamics of the car, but here I am several months later still feeling like I'm driving a completely different car (when it comes to braking). I'm still letting up on the accelerator at the same places I have been for years only to find that I'm left hitting the brakes HARD as I approach stop signs and intersections that I used to EASILY come to a full stop at without so much as thinking about the brake pedal. It's almost as if the "Standard" setting has taken on the "Low" setting parameters... although I can't imaging it being any lower unless the new "Low" setting really means "disabled."

Not only is dramatically changing the way my car BRAKES a terrible idea, it's DANGEROUS! PLEEEEASE can I have my "FULL" regenerative braking back?!
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Comments

  • You didn't say what car you have or what software version you have, but I have not had the same experience. My regenerative braking is just fine (2019 Raven, version 2020.28.5).

    As far as being dangerous is concerned (or as you put it, "DANGEROUS!"), I must say I find that a bit overdramatic. And if you have to hit the brakes "HARD" every time you stop, maybe you should get your car checked out.
  • I have an 8/17 S100D with 32.1 but haven't had a RB problem with any version. Might want to schedule an appointment with your local SC.
  • 2014 Model S 85 - Software version 2020.24.6.11 3f9850467abb
    Owned it since it was new, and have loved it until a few months ago when the regenerative braking behavior changed... I'm being dramatic because it is a DRAMATIC change. All of a sudden one day it went from having strong regenerative braking to very weak regenerative braking. Changing the way the car brakes without warning isn't dangerous??

    There are complaints from other drivers experiencing the same thing since updates back in March and April, so I know it's not just me. Unfortunately, Tesla doesn't seem to care, and their only response is "Technician reviewed vehicle settings and found regenerative braking is turned on." Not super helpful. I just want my strong regenerative braking back... is that too much to ask?

    At least part of the issue in the regenerative braking problem comes from the behavior where the amount of resistance from regenerative braking is now being reduced as the car slows down. For example, when you're driving at 75mph and you let off the accelerator the car slows but not much since the resistance is capped at 50 ot 60kw(?). That's how it's always been at higher speeds, but at lower speeds... say 40mph the car would quickly slow down and stop, and life was wonderful. However, now as the car slows down gradually, the resistance is also now programmed to automatically decrease resulting in the car traveling MUCH farther than it would otherwise travel had the resistance been allowed to stay at max until the car basically came to a stop.

    I know Tesla was messing around with the regenerative braking settings a while back because we have 2019 X that had a few dramatic changes to regen braking around the same time as it began with the S. At least the X got it's full force regen braking back in one of the updates, but sadly our S has not, and it sounds like there are many others who are experiencing the same issue. If it's not you, consider yourself lucky.
  • Not sure this is real.

    Does not jibe with 8 years experience.

    Approach with caution.
  • stevens.socal_98505910,
    You mentioned nothing about how your regen. is set. Did you check you regen. setting? Could it be set to low?
  • Excellent point, @AJP. A drastic change in regen braking where the car is markedly different to the point of safety concerns sounds unusual and atypical. While I miss the "original" regen of my 2015 MS when it was new, the changes in regen for my car have not left me feeling unsafe. If anyone with a similar 2014 model has noticed this as well, it would be interesting to hear.
  • It’s not so much programmed to decrease regen at reduced speeds. Those are the laws of physics of converting momentum to energy. 60 kW has always been the approximate maximal value. Regen is limited with temps to around 60F, so if there was any overnight cold soak to temperatures below that, you’d see reduced regen for a significant amount of time until the battery warmed up. These temperature thresholds have been raised over the years.
  • 2014 S85 V2020.24.6.11 SoCal

    I have not noticed any appreciable change in regen in the nearly 6 years I've owned the car. Small tweaks perhaps, but nothing dangerous.
  • 2014 S85 V2020.24.6.11 MD

    I’ve driven to the Blue Ridge Mountains recently and I didn’t notice any difference in regenerative braking.
  • My regen has been fine this summer. This past winter it was useless and I couldn't drive the car in the mountains without any engine braking on the 40 mile and 5000 ft vertical drop.
  • This sounds like a software bug which hits particular years and configurations. I had a number of those with my S over the years which updates eventually corrected but braking is always serious. Going down a long grade and having to ride the friction brakes is bad for the car and could be considered “coasting in neutral”. There is a reason why that is illegal. You could have data corruption in part of the O/S. Tesla used to be good about surgical overwrites at the SC but doubt they have anyone capable of that today, but it’s worth a try.

    I won’t insult you by asking if you have done all of the usual resets. Of course you have. Have you tried a more drastic step of using factory reset? This wipes all user settings and may not fix the problem but it might cause the Ubuntu O/S to rebuild enough caches to get rid of the corruption.
  • I have a Model 3 and have ZERO doubt that something big changed with my last update (on 2020.36.11 ccacdb181f16). I can no longer "regen-brake to a stop" behind a car at a stoplight and have been forced to use my brakes about 10x as much as I used to. This is a TERRIBLE change. I hope Tesla will either fix (bug) or explain why.
  • i have 36.11 and there were no changes to how regen operates. Schedule service or report a bug if this is whats actually happening to you.
  • @rwinchester - Did you check your settings to make sure brake hold is still enabled? Software updates have been known to change settings, though it’s uncommon.
  • @rwinchester is right. I too have noticed a relatively big change in the regen after 2020.36.11 (I am on 2020.40.4 right now).

    I drove complete in town and highway trips without ever having to use the brake and now have to use it when coasting to a stop behind a car almost everyone.

    Both the rate at which the car slows from a high speed is slower and the distance it rolls without brake or accelerator pressed is longer.

    It appears Tesla may be trying to bring the car to a smoother stop but, honestly, I don’t like it. I am used to feathering the accelerator the perfect amount to come to a stop exactly where I want to.

    My wife who never notices anything with cars even noticed and commented.

    I hope it’s a bug and not permanent. If it is permanent then Tesla needs to introduce a third setting for regenerative braking: “high”.
  • OP, why are you still on 2020.24? I too have a 2014 S85 and I am currently on 2020.36.11. Prior to that I was on 2020.36.4. No noticeable difference in regen and I live in a hilly area of CT and would certainly notice an increase in brake usage. Also, IMHO you are being a bit dramatic. Even if you lost all of your re-gen, the car would still stop via the brakes, just like every other car on the road. So it is not "dangerous". It is only dangerous if you don't have the ability to adapt.
  • we are forecast for 3-5 in. snow tomorrow and without low regen setting I am going to be very very careful. Minnesota, 2020 S long range plus.
  • @neilhamrin_92889139
    We had a foot yesterday and I didn’t even think to lower the regen, in retrospect.
    One because the temperatures did that already and two, because the roads weren’t that slippery.
    It will be interesting to see how the new version handles the updated regen.
  • > @jordanrichard_629778 said:
    > OP, why are you still on 2020.24? I too have a 2014 S85 and I am currently on 2020.36.11. Prior to that I was on 2020.36.4.

    I'm still on 2020.36.3.1 with my 2015 S85D. I have "not-willing-to-be-a-guinea-pig," I mean "standard" selected for updates.
  • > @jordanrichard_629778 said:
    > Even if you lost all of your re-gen, the car would still stop via the brakes, just like every other car on the road. So it is not "dangerous". It is only dangerous if you don't have the ability to adapt.

    Au contraire, JR. It IS dangerous. Where I live, there are 40 milelong hills, not the east coast pimples you call hills. Without regen, one would burn through their brakes on these downhills. ICE cars have the ability to downshift. EVs have, and need, regen for the same reason.
  • barrykmd, I too have standard selected. From what I have read 2020.40 is already out.
  • Regen braking should be improved.
    Recently, after upgrading to 2020.40 my regen braking was reduced drastically. If this is connected to the battery temperature, then it can be easily corrected by using the excess power to heat the battery instead of limiting the braking. This way the battery is conditioned faster. Other potential uses for excess power generated during the braking can be used for interior heat.
  • @Teo_Dor Go work for Tesla if it’s so easy. Don’t be ridiculous.
  • Teo_Dor, what are you talking about...…?

    Regen has always been connected to the temperature of the battery pack. How the battery gets heated up is via electrons going in and out of the pack. Excess power is not limiting braking, it is the temperature of the pack. Tesla has already made significant changes like the scheduled departure feature to have the battery warmed up via charging", to either illuminate the need to limit the amount of regen or reduce the amount of time that there is a limitation.

    The heat for the interior in a S, X and up until very recently, the 3 comes from a resistive heater.
  • My 2018 model 3 (2020.48.30) has this same issue. I went from almost never using my brakes to having to use them all the time as the regen braking is much weaker. My setting is on Standard.
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