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Less regen on 2019.40.2?

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Early Friday morning, software 2019.40.2 was installed. I drove to work as normal around 6:15am. It was about 55F in my garage, but I noticed reduced regen for about half of my ~15 mile trip to work. I thought that was kind of weird, but then saw it again when I went to leave from work with temps also in the mid 50s. I used ScanMyTesla to check the battery temp and it was around ambient. I decided to see when I could get full regen.

I monitored the battery temperature and saw that the average cell temp rose to 66.6F before full regen was available. Has anyone else experienced this? I'll see if the car does the same song and dance today when I drive it.

Edit: forgot to mention that the battery was at 90% when I left my house and 80% when I left work, so SoC should not be an issue.
 
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Just updated to 2019.36.2.4 which I suspect is just a version branch for UK with just a few bug fixes and thought my regen braking had gone. It caused a bit of panic braking. Got loads of dots on line under speedometer. Only had car 2 weeks and its not as good as it was after 2 upgrades (Original 2.1 then 2.3 now 2.4). Tesla really need to get their release notes sorted or there will be smashes caused by minor changes that are undocumented.
 
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There has definitely been a change to the threshold temp at which regen will start to be limited. From what I have seen, the temp is now below 50- 55 deg F or so. Previously, it was much lower.

My guess is that Tesla has determined that this change will increase battery health. But, it sure decreases range this time of year.
 
I monitored the battery temperature and saw that the average cell temp rose to 66.6F before full regen was available

yeah seems consensus so far is that something did change like the threshold for this cold weather protection. it's a little annoying cause 55F (seems like this temp keeps coming up and what I've been experiencing) is not really that cold.. i dont have you're version but it started with the 36.2 one
 
Aha! it's not just me then... I installed 2019.40.1.2 yesterday morning (UK) and when I drove the car in the afternoon, I was convinced that the regen was significantly less! I don't remember having to use my brakes that much, well, ever since I got the car!

I checked all the settings to see if something had been defaulted by the install, but everything looked reasonable, just no where near as much regen at higher speeds. It seemed to cut in much later, at lower speeds, otherwise the car would just roll along like an ICE at higher speeds, without any noticeable braking effect when I lifted my foot from the accelerator.

I have to say, I'm disappointed!I really prefer the one-pedal driving technique, and was hoping to save on replacement brakepads! ;)
 
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on the instrument cluster, the energy graph.. the regen portion will have yellow dashes for the restricted range portion. you will also get a temporary yellow caution triangle there when it is changing the amount of restricted regen.. so, when car is finally warmed up you will see that, then the yellow dashes disappear
 
Early Friday morning, software 2019.40.2 was installed. I drove to work as normal around 6:15am. It was about 55F in my garage, but I noticed reduced regen for about half of my ~15 mile trip to work. I thought that was kind of weird, but then saw it again when I went to leave from work with temps also in the mid 50s. I used ScanMyTesla to check the battery temp and it was around ambient. I decided to see when I could get full regen.

I monitored the battery temperature and saw that the average cell temp rose to 66.6F before full regen was available. Has anyone else experienced this? I'll see if the car does the same song and dance today when I drive it.

Edit: forgot to mention that the battery was at 90% when I left my house and 80% when I left work, so SoC should not be an issue.
I have the exact situation you do, including the commute length and the garage temperature. I noticed the same thing with the last software update. Basically, the entire winter I will not have full regen except for a long trip. This is the fourth major change to my car since I got it nearly four years ago. It was supposed to get better with the updates, not worse (autopilot is more of a nag now, supercharging is much slower, lost about 5-10 miles with the update, and now the regen restriction.)
 
This morning was the first opportunity I had to test scheduled charging. It worked, and I was fully charged when I left for work. It was a cold morning (around 25F outside) but the battery was 75F when I pulled out of my garage with full regen available right away. I'll still have to deal with less regen on my drive home, but scheduled charging is a pretty nice new feature.
 
Really noticed the limited regen today, temp was 11C in UK and it took a good 15miles until I got regen back to being useful.

Also since last update my back left rear window goes down a bit on opening door and doesn't go back up auto, I had told the kids off for messing with the windows ....felt bad as it wasn;t them.
 
If they are reducing the charge rate to 70kw on average up to say 50% of battery capacity and down to 50kw up to 70% capacity then down to 30kw above that.... then it makes sense that they would reduce regen to the same amount.

Not that I am happy about it, for them to have made these drastic adjustments looks like the battery data has not gone how they thought it would.
 
I don't know if it is 40.2 or 40.2.1 as I received both wishin half an hour of each other, but yeah, much reduced regen.

As others have mentioned, this is a huge setback in what sets this car apart from the ICE counterparts, the one pedal driving and lack of need to use brakes.

Wife and I left the garage (10 degrees C) last night, drove with plenty of yellow dashes visible and not much regen on the highway (110 km/h) to Starbucks 15 km away, and then plugged in at a nearby 69 amp 14 kW level 2 charger for about 15 minutes, sucked up 15-20 km of range in the car, and still had plenty of dashes visible upon unplugging. Got back home after another 15 km and still had yellow dashes on half the cluster display. Before these updates I am pretty sure there would be no reduction of regeneration after this situation. And it was only 2 degrees Celsius; quite balmy for this time of year. I wonder if we will have reduced regen for an entire 300 km highway trip in typical temperatures for this time of year (-10 C). I'll find out next weekend.

What I don't know is: Is this happening to all cars? AP2/2/5 and AP3? or just the older cars (AP1)? Anyone with a 2017 or later car noticing the same reduction of regen?
 
for me it was 36.2 that did this, when scheduled charging arrived.

here the overnight low is about 50F/10C this time of year and im getting 4 yellow dashes every day now in the morning. on rainy days where the high doesn't get above 60 it will also be there in the evening when i go home.
 
I am in SF Bay Area. Here its comfortable 60 degrees, but regen braking is completely off. The entire pleasure of driving model S has gone for a toss. If I could roll back to earlier version I would. This is a definitely because of a bug in the latest software update.