Regen braking stopped working [2021]

[XPsionic]

Just drove 3000 miles from LA through Utah to Denver and back with huge elevation changes, experienced a few different "regen limited" scenarios. How it seems to work is a combination of 3 factors all mixed in together. 1. Current battery % 2. Pack temperature 3. Time spent regenerating recently

1. If battery % is above 60% then it'll be possible to see "regen limited" when pack temp is low and/or if you've been going down a long hill. At 100% battery you'll not get any regen at all. At 90% battery you'll get maybe one round of 70mph-0mph regen before it temporary becomes limited for a minute or two.

2. If it's cold out you'll always get "regen limited" especially if you don't precondition.

3. If you're going down a lot in elevation you'll initially get full regen, then it'll start to become limited after something like 1000-1500 ft elevation loss. This is very much dependent on battery % and how steep the hill is. Below 60% with a warmed pack the car seem to be able to regen without any limits, above 60%, even with a warmed pack, especially at above 80%, regen will only last a few minutes before being limited.

TLDR: If you want full regen all the time and you don't need max range for your car, try keeping battery to below 60% and precondition before you set off in the morning.

 

[MikeyC]

Well there you go... there is no such thing as a "hill" in FL.

Mike

 

[rpiotro]

Well there you go... there is no such thing as a "hill" in FL.

Mike

Pretty much so anyway.

Highest Elevation in Florida

Its highest point has an elevation of 345 feet (105 m), while its lowest point is the waters of the Atlantic Ocean and Gulf of Mexico, which are at

vacationidea.com

 

[Jiveman]

I'm so glad I found this thread. Completely validates what I was experiencing on 4/29. After sitting parked for 2 hours (normal ~70 degree day in shade also in San Diego btw), not charging at all that day. I drove out of the parking lot and almost hit the car at the stop sign as the regen braking stopped working. I was at ~50% battery. I test it a few more times, and it began to work mid-drive. A few seconds later it again stopped working, then a minute or two later started again. I decided to call teslas 800 number to report the issue. The agent "Claudia" refers me to the Kearny Mesa service center since it's a safety concern.

After more than a week I get a message in the Tesla App saying my cars ready for pickup. Once there they explain they reviewed the logs and everything was fine. I asked why regen braking stopped working, they said it was because I was braking too much!? I explained it was the first stop out of a parking lot after the car sitting for 2 hours. I verified regen was enabled "standard" in the settings.

The manager tried flashing his laptop at me with some partial graphs (wouldn't actually let me read them) saying the data checks out and everything is fine. I explained again what happened and he couldn't explain why it was not engaging after sitting for 2 hours. Every tech I speak with doesn't seem to know basics of the ticket. The manager did escalate the issue, but about a day later updated the service with a note that "escalation resulted in same conclusion". Without explaining why regen wasn't working out of the parking lot, or why it re-engaged and dis-engaged mid drive as well.

I also did a bug report and gave them a ~15min resolution time frame so they could zero in on the logs.

What I find super frustrating is the manager Luis, doesn't seem to care what happened as a customer. He continues to just say the logs say X happened. He won't show me the logs, nor will he allow me to speak with the "escalation" Engineers. He keeps saying "its not a safety concern", not even acknowledging changing the vehicles response mid-drive in-fact IS a safety concern for most people.

 

[Jiveman]

I'm in San Diego, have a pre-ordered 2018 M3LR and just began having this issue on 4/29. I took created a bug report, called Teslas 800 number while driving to ensure they had the data to isolate & troubleshoot the issue. The agent Claudia advised me to take it to the Kearny Mesa service center. After about 2 weeks they called me to notify me my car was ready. Their explanation was that the system indicated I was over-using regen braking and it shut it off to protect the battery. I explained the car had been sitting garaged for a day and only made a 14mi trip. It hadn't been charged recently, battery was at 52%, no warnings etc.. on the screen. The regen braking failed after leaving the parking lot (almost hit a car) where it had been sitting for 2 hours in shade on a 70f day. So their diagnosis didn't make sense to me.

The manager brought his laptop out and started waving it around "showing" me some graphs that supposedly confirmed his diagnosis. I asked to closely look at the data to which he said he's not allowed to show me, and that some data was missing (unexpectedly). After I explained time and time again what JUST occured he said he would escalate the issue to upper engineering. I believe a few days later they "confirmed the original diagnosis".

I asked to get a copy of the data because it was flat out wrong and was really concerning me. Luis (manager) started getting irate and saying there is no way I could get this data. He kept insisting it wasn't a safety concern and that engineering confirmed "everything is ok".

About a week after relucantely taking back my car it happened again. I had my fiance recorde it happening while I was driving. So I took it to a different service center hoping it was maybe a "bad apple". Just had to pick up my car today and their new diagnosis is that it's because I changed to aftermarket HRE 20" wheels. Pasting in the verbiage on the invoice below. Even the poor service tech that was reading the notes didn't believe what he was reading. So the problem seems to be systematic throughout Tesla.

Concern: Customer states that his regen braking gives out intermittently and is concerned with driving the vehicle
The reason regen is not operating as the customer was used to is because the aftermarket wheels and different size tires.
Please advise that this is normal and if they would like to return to original functionality then they would need to use stock wheels and the tire size printed on the label inside the door jam.

 

[XPsionic]

Update to the latest software, the car will now add physical brakes when regen is limited.

 

[Jiveman]

Update to the latest software, the car will now add physical brakes when regen is limited.

I find it extremelly odd that not a single Tesla Technician mentioned this in the 7 interactions I just had with them regarding regen braking. Do you know what version introduced this new behavior? I remember even mentioned that the car really should never alter braking behaviour based on battery status to Luis (Tesla Manager) who replied "then where would the energy go?! It's physics!", smdh. While I'm glad to see this is a step in the right direction, it really makes me wonder if they're trying to cover up a mistake. Really feels like we're all driving Betas and I'm fed up with it.

 

[RayK]

Do you know what version introduced this new behavior?

I believe that 2022.16.0.2 is the one with this option.

ref: Tesla updates car software to start applying regular brakes when regenerative is limited
ref: Tesla 2022.16.0.2 update includes navigation energy prediction, blended brakes & more

 

[SDsean]

The fact there is no straight answer or communication from Tesla on this is concerning. The change is actually dangerous as drivers get used to the breaking when foot of the pedal and instead the car launches forward!. It's been happening a lot lately these past weeks and hence whey I looked it up. I'm sure if I go to Tesla they'll give me some bs, but I was hoping for a fix - some software update or some recalibration they had to do. Not happy with all these explanations about cold batteries as this is only happening now 3 years after I bought it.

Jumping on to this thread to keep track of what's happening. My Model 3 is having the same problem and it's completely inconsistent. Regen works and doesn't work whenever it feels like it. It's not the cold because we live in San Diego. It's not the battery charge, because it happens at all levels. They thought it was the tires, but I replaced those and it still happened.

I'm not sure what's going on, but I am equally frustrated that Tesla keeps telling me there's nothing they can do. Unfortunately the car refuses to duplicate the problem with a service tech in the car. But I do take video every time it happens and submit it. I've also been date/time stamping each time it happens, so Tesla service has something to go on.

We've had the car for 4 years without a problem. But now something is busted.

It's in service, AGAIN. I will let y'all know what they come back with. My guess is, they're going to say there's nothing they can do (AGAIN). And that it's normal operation, which it's not.

 

[SDsean]

I find it extremelly odd that not a single Tesla Technician mentioned this in the 7 interactions I just had with them regarding regen braking. Do you know what version introduced this new behavior? I remember even mentioned that the car really should never alter braking behaviour based on battery status to Luis (Tesla Manager) who replied "then where would the energy go?! It's physics!", smdh. While I'm glad to see this is a step in the right direction, it really makes me wonder if they're trying to cover up a mistake. Really feels like we're all driving Betas and I'm fed up with it.

Yeah, if they decide physical breaking is the fix, that's going to be a serious problem. There goes our range and our break pads.

 

[jjrandorin]

It's not the cold because we live in San Diego

People make this mistake all the time (thinking that the car cant be cold because we are out here). Yes, the battery gets cold here. I work in north county, and have had a model 3 for just under 4 years now. I commute from Temecula to North County for work.

In fall / winter, not only does the battery get cold (not cold enough to display snowflake but absolutely cold enough to impact regen), it can take up to 20 miles driving at freeway speeds of 80MPH + to warm up enough to not display regen dots.

So, "its not cold because I live in San Diego" is absolutely 100% not accurate.

 

[SDsean]

People make this mistake all the time (thinking that the car cant be cold because we are out here). Yes, the battery gets cold here. I work in north county, and have had a model 3 for just under 4 years now. I commute from Temecula to North County for work.

In fall / winter, not only does the battery get cold (not cold enough to display snowflake but absolutely cold enough to impact regen), it can take up to 20 miles driving at freeway speeds of 80MPH + to warm up enough to not display regen dots.

So, "its not cold because I live in San Diego" is absolutely 100% not accurate.

OK, I'll rephrase ... in the first 3 years of ownership, it never got cold enough in San Diego for this to be an issue. Regen worked perfectly.
Now (during the summer in San Diego) it's not working.

The point is, Tesla blaming the cold for my regen not working is bullocks.

 

[Gasaraki]

I have not had this "limited regen issue".

 

[SDsean]

The fact there is no straight answer or communication from Tesla on this is concerning. The change is actually dangerous as drivers get used to the breaking when foot of the pedal and instead the car launches forward!. It's been happening a lot lately these past weeks and hence whey I looked it up. I'm sure if I go to Tesla they'll give me some bs, but I was hoping for a fix - some software update or some recalibration they had to do. Not happy with all these explanations about cold batteries as this is only happening now 3 years after I bought it.

Really frustrating. Tesla service is telling me that the front tires having more wear than the rear tires is causing the regen problem. Because the car is RWD, I am having a hard time believing this, as there is no motor and no inverter attached to the front wheels.

I love my car, but this is getting really frustrating. And it appears they are just making excuses to get me to go away.

 

[yepeekai]

Me too! There are inconsistencies with regen braking for the last few months... On the same drive, regen works and then, out of nowhere, get reduced to the point you think there is none and then it comes back and on and off randomly... It does work most of the time but it happens quite often that there is mostly no regen. SR+ 2020 here.

 

[tesluv108]

I’d like to weigh in here. Rewind to 2017 I had a 2013 p85 rwd. The car regen was so brutal I had to toggle it from standard to low because at that time it would borderline throw your head from how hard it would brake. Now, fast forward to 2022- I have a p90d late 2015 build. I was/ have been impressed at the tweaks Tesla made to the regen braking. While some think it’s too mild now, I consider it just right. That was BEFORE this week. So I’m going to an appointment Monday at the battery is at 39%. I have a large hill in my neighborhood I usually go down and normally have to PRESS the accelerator to make it down because the regen Is fighting the car. But this latest time the car actually rolled down the hill to the point where I had to apply the brakes manually. I wasn’t pleased and no amount of reheating / driving the car made regen increase on the way to or from the appointment. Fast forward to today, I went for a ride at 67% soc with outside temperatures around 54 degrees. Again the car is not acting like it normally does with regen comparing it to the entire time I’ve owned this car in 2022. I’m wondering what could have suddenly changed. I did get a software update a few days ago but didn’t install until after the regen issue. The only other time I had any type of issue with the regen is when the coolant heater went and there was no regen- but at least I knew I didn’t have it. Now regen only works sporadically and definitely not at higher speeds like it usually does slowing the car as you gently let off the accelerator. I know I can’t be the only one having this issue! I will monitor again tomorrow on thanksgiving leaving the house with a 75% state of charge and driving over 100 miles tomorrow.

 

[tesluv108]

I’d like to weigh in here. Rewind to 2017 I had a 2013 p85 rwd. The car regen was so brutal I had to toggle it from standard to low because at that time it would borderline throw your head from how hard it would brake. Now, fast forward to 2022- I have a p90d late 2015 build. I was/ have been impressed at the tweaks Tesla made to the regen braking. While some think it’s too mild now, I consider it just right. That was BEFORE this week. So I’m going to an appointment Monday at the battery is at 39%. I have a large hill in my neighborhood I usually go down and normally have to PRESS the accelerator to make it down because the regen Is fighting the car. But this latest time the car actually rolled down the hill to the point where I had to apply the brakes manually. I wasn’t pleased and no amount of reheating / driving the car made regen increase on the way to or from the appointment. Fast forward to today, I went for a ride at 67% soc with outside temperatures around 54 degrees. Again the car is not acting like it normally does with regen comparing it to the entire time I’ve owned this car in 2022. I’m wondering what could have suddenly changed. I did get a software update a few days ago but didn’t install until after the regen issue. The only other time I had any type of issue with the regen is when the coolant heater went and there was no regen- but at least I knew I didn’t have it. Now regen only works sporadically and definitely not at higher speeds like it usually does slowing the car as you gently let off the accelerator. I know I can’t be the only one having this issue! I will monitor again tomorrow on thanksgiving leaving the house with a 75% state of charge and driving over 100 miles tomorrow.

So as others have stated this is definitely a temperature issue. On the model S there will be 4 orange lines on the regen screen until the battery warms up.