Possible explanation for recent range loss and "degradation"

Possible explanation for recent range loss and "degradation"

Lots of threads and consternation about recent firmware affecting the car's range and efficiency. Oddly, it only affects a subset of owners. Any chance that the folks who are affected have the new wheel configuration set to the less efficient wheel choice? We know that new firmware now offers Wheel Configuration under the Service tab. Obviously, this will input distinct efficiency rate constants depending on wheel choice. I'm guessing that people who have seen their rated range suddenly drop a few percent have the larger diameter rim chosen. So maybe no CLASS ACTION this week?

Hp.1193 | October 19, 2019

Isn’t is auto selected? Unless you changed wheels after buying the car ?

Hp.1193 | October 19, 2019

It *

Bighorn | October 19, 2019

Suppose it were pre-selected and until now both 18 and 20 inch wheels were given the same efficiency rate constant of say 235 Wh/m. Now that there are multiple options, presumable the 18" choice would still be 235 Wh/m, but the 20" might be 260 Wh/m and the 19" somewhere in between. That would explain why some are seeing a different rated range spontaneously and others are not.

gballant4570 | October 19, 2019

Bighorn, I already checked my car. The correct wheels (18") are chosen. My 90% charge these days is estimated as 260-265 miles, and my 100% charge comes in at around 298 estimated miles.

However, if I drive in the neighborhood of the EPA basis (wh/m) nothing has actually changed - only the estimated miles for SOC. I can still get 310 or better out of a full charge.

gballant4570 | October 19, 2019

My conclusion has been that my car has not experienced battery degradation or range loss, but that it does not estimate available mileage based on SOC as well as it once did.

Bighorn | October 19, 2019

Thanks. My estimate has been all over the map this past year over the course of 40k miles, down and up. I've always chalked that up to the inability to measure battery capacity precisely. This particular hypothesis applies more specifically to those who claim a sudden, significant range change brought on by a recent FW update.

gballant4570 | October 19, 2019

My mileage estimate discrepancies started suddenly in a manner that easily could have been attributable to a software update, and perhaps were associated with one. However, real world data shows as I stated above.

I can see why people conclude that they are losing range and/or battery capacity, but a closer look reveals that is not the case - at least with my car.

A wrong wheel diameter choice could have also showed up that same way, but I checked and the wheel choice in my car was and has been correct.

h2ev | October 19, 2019

One of the first things I did setting up the car prior to driving it out of the Tesla center was to change the display from miles to %. Ignorance really is bliss.

I did charge my car to 100% a few weeks back and I flipped it over to miles which reported 306 miles (dual motor non P with ~18k miles). Perhaps I’ll charge it to 100% tomorrow and see what it now says on the current version.

jfaubl | October 19, 2019

My 90% was 274 and now is 264. I'm sure this is a software issue and not a true loss of range. However, I always tell people that the true range is 250 not 310. 250 on the highway at 80 and 250 around town since I floor it all the time,hey I got the performance I'm going to use it.
I don't drive a lot but I did use 40% of the battery yesterday. Usually 10% is 25 miles. Yesterday 40% was 40 miles.

Has anyone tested a longer drive to see if range is less?

jfaubl | October 19, 2019

On and this is not a direct attack, but people who say set it to percentage and don't worry have straw manned the original complaint. If 100% truly became 50 miles I'm sure people wouldn't have the same response.

I do believe this a software glitch and not something permanent.

bheck11 | October 19, 2019

Along these same lines, I am now worried about the lack of sudden range loss in our mid-range Model 3.

The car is approaching its first birthday and has about 8500 miles on the odometer. Near as I can tell by calculating based on battery percentage and miles left, it has lost about 4 miles of range. Based on a rated 260 mile range, that's 1.5%. For those more scientifically inclined, that's within the what we assume is the likely measurement error range, so we can't even clearly demonstrate any loss at all.

Oh, we've tried to lose more range. We've charged it up to nearly 100% before long trips. We've driven it for miles and miles between charges. We've supercharged when needed. We've installed update after update and are now on the latest one available. Mostly, after figuring things out in the first few weeks of ownership, we've completely ignored the range and just driven the car. Clearly we're doing something wrong, as we are left with no complaints about battery degradation.

Tesla should fix this right away!

(All tongue in cheek, and not meant to dis those who truly have suffered range loss for whatever reason.)

steveishere | October 19, 2019

Mine is 8'' aero wheels. Currently 241 at 80%. It was at 296 when I charged to full for a road trip last week.

Dual motor long range, delivered at 9/30/2018, about 18k miles in.

Mike UpNorth_ | October 19, 2019

Checked mine recently. 309. AWD ~10k miles. 1 year.

Mike UpNorth_ | October 19, 2019

Probably 315 after I inflate with nitrogen :)

Joshan | October 19, 2019

Software cannot cause battery degradation... stop talking nonsense.

Software can also be undone if they desire. Its not like it burned up 5% of your battery.

FISHEV | October 19, 2019

“Software cannot cause battery degradation... stop talking nonsense.”Joshan

Don’t see where @Bighorn made that claim. Or did you misread my message above?

zerogravitydrgn | October 19, 2019

I too thought it might be related to the wheel size setting

vmulla | October 19, 2019

It's not wheel size. I think it's just loopy software update. Should settle itself over the following updates. The current numbers range vs consumption numbers just don't make sense.

vmulla | October 19, 2019

Here's another example from me. I started with 90% as usual and the starting range was 273 miles. I had the usual 1 - 1.5 hrs stop. This time it was raining so the consumption was on the higher side.

vmulla | October 19, 2019

I just did the math, that's ~33 miles of unexpected loss for a 1 - 1.5 hr stop.
I'm just saying the software estimate of the range/consumption in this update Is noticeably off. I'm not at all worried about battery health.

Joshan | October 19, 2019

cant believe I am going to say this... I did misread your post fish. Plz disregard, my bad.

kevin_rf | October 19, 2019

While I do feel that I lost some displayed range with the v10 update, some of it is fall temperatures. Today the car was sitting at 215 miles, it was a little warmer out, all week has been cold and it's been sitting at about 210. Before v10 it would usually be about 220 on the warmer mornings.

LR AWD new 18" Continental aeros 29k miles 70% charge and red (which definitely holds faster electrons than other colors).

Btw. I had been charging at 11pm for the TOU. With winter coming, based on my typical driving I have changed my start time to 3am to get charging to finish closer to 7am. This way, the battery hasn't been cold soaking for 5 to 6 hours before work. Curious if it will have an impact since the battery will still sit and cool for an hour, maybe two.

richard | October 19, 2019

Today I drove Model 3 about 60 miles at speeds of 60-75 mph and city driving for a total of 76 miles but my battery range started at 250 and ended at 150 so battery used 100 miles, Temp outside about 50, no air conditioning, used seat heater and temp set to 69. No fast acceleration. Car was new May 2018. Is this normal? Software has ben updated as it becomes available.

rsingh05 | October 19, 2019

My 90% used to be 278. Now it’s 270 (and 100% the one time I fully charged recently was 299). I think it’s related to how the software estimates the ideal range.

I have the 3P with 20” wheels so the new 300mile estimate may be closer to reality than 310. If that’s the case I’m not worried.

Interestingly if you use Tesla api to get your cars range (needs some programming ability) it will give you two metrics. One is the ideal range, the other is the estimated range. The car and the Tesla app report the ideal range and that’s the number that’s dropped.

vmulla | October 19, 2019

It's understandable if the estimated range dropped because of some unique usage data, but I'd think ideal range is going to be based on the same factors for all cars. What you just shared is causing more confusion.
Both the numbers you mentioned are just software generated and do not suggest real degradation - so I'm just going to wait for a software correction.

amceachin | October 19, 2019

I have 18" aeros in my LR RWD car, and have the correct wheel config on my software. I bought the Stats app somewhere around 13k miles just before I went on a two week road trip. I was curious about tracking the efficiency when driving up and down the 5. As by-product of the app, it tracks "battery health" which is really just the best guess of the stated full range of the battery. I noticed both a lot of day to day noise, but a slow and steady linear decline. You'll see this from the link (if I did it right): You'll also see a clear 3 to 5 mile dip around 17k. I'm not worried about the health of my battery, and chalk this up to some sort of experimentation with Tesla. I do now, however, get consistently between 295 and 299 for a full charge instead of 305 to 310 (note: I never saw the 325 bump).

h2ev | October 20, 2019

After a short drive this morning, my car was at 80%. Flipped it to miles display and it was 240 so 100% = 288, no need to actually take it to 100%. Damn I thought my car was special. Back to % it goes. As has been said to me before, Tesla will do Tesla does and I will like it.

Temps are dropping. It was 40F on that drive. More annoying than battery "degradation" is dealing with the constant fogging glass once again.

Bighorn | October 20, 2019

240/0.8=300. Maths.

Bighorn | October 20, 2019

It makes one wonder how many people are “mad” because they simply lack fifth grade math skills.

Hp.1193 | October 20, 2019

Simple proportion

(% displayed/100) times (miles displayed / x)

Or in your more equivalent, simplified case:
miles displayed / % in decimal form

MAB1980 | October 20, 2019

I don’t believe there is any zero day range loss caused by the code push. I suspect they changed (maybe improved) how range is predicted.

PteRoy | October 20, 2019

I charged to 100% last night to see where I’m at. Car says 349km(216miles). When I bought the car the website said 384km(238miles) I think and now it says 402km(249miles).13,000kms(8000miles) on the car since June.

jfaubl | October 21, 2019

@rsingh "I have the 3P with 20” wheels so the new 300mile estimate may be closer to reality than 310. If that’s the case I’m not worried"

This may be true. I just checked this morning and I have and estimated 298 range down from 305 before this software patch. I do have a Performance. So if Tesla thinks the true range is 300 vs 310, my battery degradation is actually not so bad. 305/310= 98.3% vs 298/300= 99.3%.
So maybe Tesla has a more accurate estimation algorithm of your range and it just going to take a bit of your driving to figure out your range. I have a heavy right foot so it would be nice to have an accurate number on longer drives.

Iwantmy3 | October 21, 2019

My change in usable battery has nothing to do with any specific setting. It is based on rated range @100% multiplied by the rated consumption used by the car as I have measured it repeatedly for many months. The rated consumption has not changed, the rated range has.

As of mid September, my car was 15 months old and had ~33000 miles. I was getting 316 miles of rated range. This would correspond to ~2.7% degradation and seemed very reasonable over that time frame for that number of miles.

Since V10 arrived, my range has dropped to ~310 miles. This is a 2% degradation in a month where I have only driven 1500 miles.

So the question is why? Is due to a change in the software reducing the amount of accessible battery as Bjorn implied? Is it colder temperatures effecting the battery capacity? Or is it a sudden degradation in the battery that hit all of us at the same time (this seems very unlikely).

I have always wondered what effect temperature has on the battery capacity. I am planning to charge tonight on what may be the last "warm" night that I may see for some time. It will be interesting to see what I get.

Kathy Applebaum | October 21, 2019

I saw a significant range loss with one of the recent updates and I have 18s with aeros on a LR RWD. Before the update I was getting 308-309 on a full charge. Last two trips I got 292, with corresponding drops at 80% and 90%.

MAB1980 | October 21, 2019

I wonder if there are any model 3s still on V9. If so, it would be super if they would charge to 100%, drive to close to zero, then update and repeat. I bet the actual total range achieved would be within error margin, regardless of what is displayed.

HalliBee | October 21, 2019

I don't think it's tires either. I lost about 5 km (about 3 miles for our American friends) on the last update. I've stayed with 18 inch wheels since new. 36000 km (22000 miles), dual motor long range.

HalliBee | October 21, 2019

Wheels, I mean, not tires.

HalliBee | October 21, 2019

Wheels, I mean, not tires.

gballant4570 | October 21, 2019

Hey folks, just like your money, its just numbers on a screen.

ReD eXiLe ms us | October 21, 2019

Far as I can tell, the terms 'degradation' and 'range loss' refer to very specific things that to my knowledge no one has yet demonstrated an example of them happening specifically due to an Over-the-Air Update from Tesla to their car.

Degradation -- The batteries never charge to or beyond the ability to reach a given amount of range in any circumstance.

Range Loss -- The car no longer covers a displayed distance at a given charge level.

This is the part where NaySayers, Contrarions, FUDsters, $#0r+§, and Trolls typically start jumping up and down, shouting, sneering, and jeering about 'semantics', and stuff. Screw those guys they are all dumb.

If your car shuts down on you before reaching a destination fifteen miles or less away when it had told you there was forty-five to sixty miles of range left...? THAT is a problem.

If a car you were sold by Tesla in the past seven years can't manage even 60% of its stated range when new in what you consider 'normal driving', even though you don't do any towing, don't transport passengers who average over 400 pounds each, aren't surrounded by a mountain range, and don't observe a 'personal speed limit' of somewhere between fifteen and twenty-five MPH over any posted local limits...? You, again, have a REAL problem.

Otherwise? Dund worry 'bout it, Loosie.

Iwantmy3 | October 22, 2019

For what it is worth, I charged from 20% to 90% last night when the outside temperatures were ~58F. At 90% the car was showing 284 miles. This would be 316 at 100% and would be similar to what I was getting in September. The last times that I charged, the outside temperature was in the high 30's overnight and my range was 311 on a 100% charge and then 279 at 90% (extrapolates to 310 miles).

I am ready to blame to reduced range of the two previous charges on cooler outside temperatures. I will prepare myself for reduced range over the winter. I saw it last year, particularly on cold days. I am just surprised that it kicked in at what are still relatively mild fall temperatures.

h2ev | October 22, 2019

@Bighorn, thanks for the correction. It was early AM didn't get to sip my coffee yet.

Mad? How is mad? Since day 1 of buying the car I've ignored the miles display knowing it's more or less meaningless.

h2ev | October 22, 2019

*Who" is mad.

vmulla | October 22, 2019

"If your car shuts down on you before reaching a destination fifteen miles or less away when it had told you there was forty-five to sixty miles of range left...? THAT is a problem" @Red

Owners are trying to avoid that problem. Knowing how much the car can deliver is part of avoiding the problem.

Look at the photos I shared. I made it back home with 4% range left, when I should have a lot more. The picture shares exactly how much I drove, what my consumption was, and what the remaining charge/range was at the end of the day.

So, knowing your car's range is important to avoid trouble.

At the moment, the numbers on the screen in version10 are just not aligning for my car.

Iwantmy3 | October 22, 2019

I am looking at your numbers. You say that you took a 1-1.5 hour break during this drive.

If I apply my rated consumption of 224 w/m to your numbers with your average consumption of 265 w/m then I would expect to see a consumption of 254 miles on your 214.8 mile trip. This implies that you lost ~6 miles while stopped. This could be a reasonable loss if the car was dealing with cool down and warm-up in the middle of the drive on a cool rainy day..

I would guess that your real rated consumption is the same as mine and that it was changed from 235 w/m down to 224 w/m last spring at the same time that mine was. You should have seen a corresponding increase in rated range at the time. If your rated consumption changed by 5% with no change in rated range, then you effectively lost 5% of actual range and accessible battery kWh.

vmulla | October 22, 2019

What's the verdict if you use Tesla's own rated consumption?

Iwantmy3 | October 22, 2019

The rated consumption line on the graph seems to line up with the original 235 w/m value. It never changed.

Using a 235 w/m rated consumption, you would have consumed 242 rated miles while driving and would have needed to lose 18 miles while sitting for 1-1.5 hours. 18 miles of loss seems unlikely.

vmulla | October 22, 2019

That's all I'm saying - the numbers don't line up on V10. I've used 242 in my math instead of the 235 that you plugged in, but still..these numbers don't line up.

I do not think there's any 'degradation', simply because chemical degradation doesn't happen overnight or because of a software update.

Iwantmy3 | October 22, 2019

I don't think it's degradation either. I think that there is a combination of effects from some of the software changes in combination with cooler temperatures that have suddenly hit peoples radar. Based on my charge last night, I am only down 2.5-3%. That seems very reasonable over 16 months and 34700 miles. I expect that colder temperatures over the next few months will make it look worse but that it will get better again in the spring.

I may need to start tracking my rated miles capacity vs. ambient temperature over the winter. That should give me something new to obsess over. :)