Range dropping abruptly at end of 50+ mile commute

[insaneoctane]

I've discussed this topic in other threads, often under the "Vampire loss" pretense. Since I think there is a new phenomena here, I've started a new thread specifically for this issue....

I'm seeing a significant drop in range at work. I thought it was vampire loss because I'd arrive at work with ~204 miles of range left and I'd return to my car, 8 or so hours later, and my range had dropped to 190 miles. Recently, I've discovered that it is happening VERY quickly at the end of my commute and started adjusting my logs so I could monitor it....well, it's very interesting!

You can see that during the first 10 minutes after parking at work, there is no loss. But, then it rapidly starts losing range as quickly as 67 MPH! Within 40 minutes of arriving at work, after losing 14 miles of range, the range drop ends and then my car doesn't lose any noticeable range for over SEVEN hours. Strangely, I do NOT seem to see this behavior on my return trip home. I'm still trying to decide if this range "loss" is real and actually costs me kWh from the wall, or if it's virtual only existing in the GUI....Any insight or experience with this behavior?

NOTE: I have both Sentry & Cabin Overheat Protection DISABLED, my vehicle is either asleep or offline for the significant majority of the stay at work, and my recent "monitoring" is only keeping the vehicle awake for ~1 hour after arriving at work....

 

[chewyc]

It's been hot here in So Cal, is this a new phenomenon? Maybe Battery cooling from your commute since it stops and starts about 30 minutes after you park.

Do you immediately plug in when home? In this scenario you'd be using your utility power to cool the batteries. Would explain the one way nature of your issue.

 

[justsomeguy]

I've noticed the car range estimation is really wonky on 2019.32, or maybe even 2019.28.3.1

I'll charge to 299km, get the charge stop notification, wake up 6 hours later at 289km and arrive at work around 245km. 9 hours later I'm sitting in my car with 255km.

EDIT

Maybe it's a result of me charging to only 60% however, as I started doing that recently.

 

[Common_Loon]

I've noticed the car range estimation is really wonky on 2019.32, or maybe even 2019.28.3.1

I'll charge to 299km, get the charge stop notification, wake up 6 hours later at 289km and arrive at work around 245km. 9 hours later I'm sitting in my car with 255km.

EDIT

Maybe it's a result of me charging to only 60% however, as I started doing that recently.

Unrelated thread diversion - but if you're doing that 60% because of what Bjorn said, know that he is uninformed and misinformed on that. I'll not get off into that discussion here because I don't want to derail the thread, but that 60% can't be a coincidence Go read a bit further. LikeTesla had a great video on it.

 

[insaneoctane]

My data comes from a car that is charged to 80% SOC every night while I sleep.

 

[justsomeguy]

Unrelated thread diversion - but if you're doing that 60% because of what Bjorn said, know that he is uninformed and misinformed on that. I'll not get off into that discussion here because I don't want to derail the thread, but that 60% can't be a coincidence Go read a bit further. LikeTesla had a great video on it.

Actually I saw that video after I started doing it. My reasoning is I very occasionally have to go visit a site for work where I park my car for 4 hours at a time. It just works out that my arrival SoC + 4 hours at this charger puts me almost exactly at 90%.

Before I get hate for "hogging" a charging station, they aren't public and there's more at this location than there are EVs that use them.

 

[insaneoctane]

I'm NOT seeing a net higher consumption from the wall in my initial analysis....

 

[insaneoctane]

It's been hot here in So Cal, is this a new phenomenon? Maybe Battery cooling from your commute since it stops and starts about 30 minutes after you park.

Do you immediately plug in when home? In this scenario you'd be using your utility power to cool the batteries. Would explain the one way nature of your issue.

I saw this before it started getting hot. No I dont always plug in right away.

 

[Atari2600]

Is it the fan blowing the moisture out of your system after you park so you don't end up with a stinky AC system?

 

[insaneoctane]

Is it the fan blowing the moisture out of your system after you park so you don't end up with a stinky AC system?

Most of the days are cool enough that vent with no AC works fine in the morning commute....

 

[omgwtfbyobbq]

My guess is it's string voltage settling with a bit of balancing thrown in for good measure. I've noticed similar after I've stopped charging even if I haven't driven the car.

 

[japhule]

Is your car connected to wifi while parked at work? Perhaps data sharing uploads are happening. Maybe try turning that off and see if it makes a difference.

 

[insaneoctane]

Here's today's data. I moved the resolution of the data to every minute for 1 hour after arriving at work. Dropped 15 miles of range within 1 hour (that's 5% of the whole LR pack!)....

 

[Ol'Blue]

Contact Tesla

 

[insaneoctane]

Contact Tesla

Yes I do want to do this but struggle with the best contact approach. Calling support generally results in then telling me to take it to my SC (in my experience), but the SC seems less "interested" in figuring this type of problem when they are backed up with plenty of more tangible car issues to repair...
I really do think engineering should review this data if I had a contact...

 

[AlanSubie4Life]

I'm NOT seeing a net higher consumption from the wall in my initial analysis....

My guess is it's string voltage settling with a bit of balancing thrown in for good measure. I've noticed similar after I've stopped charging even if I haven't driven the car.

I like this balancing theory. Maybe some of the series cells in your pack are weaker so they get overly discharged and the system has to work to balance them once the vehicle is resting.

But then the “no higher [wall] consumption” would not make any sense - in fact if that were true it would suggest this is all imaginary and your driving Wh/mi should look nice and low relative to before you started seeing the problem.

1) what is your 100% extrapolated full charge in miles?

2) have you tried charging to 90-95% and repeating the experiment?

3) when exactly did you start noticing this? Correlated with a software update?

 

[BZM3]

I've discussed this topic in other threads, often under the "Vampire loss" pretense. Since I think there is a new phenomena here, I've started a new thread specifically for this issue....

I'm seeing a significant drop in range at work. I thought it was vampire loss because I'd arrive at work with ~204 miles of range left and I'd return to my car, 8 or so hours later, and my range had dropped to 190 miles. Recently, I've discovered that it is happening VERY quickly at the end of my commute and started adjusting my logs so I could monitor it....well, it's very interesting!

View attachment 452699

View attachment 452698

You can see that during the first 10 minutes after parking at work, there is no loss. But, then it rapidly starts losing range as quickly as 67 MPH! Within 40 minutes of arriving at work, after losing 14 miles of range, the range drop ends and then my car doesn't lose any noticeable range for over SEVEN hours. Strangely, I do NOT seem to see this behavior on my return trip home. I'm still trying to decide if this range "loss" is real and actually costs me kWh from the wall, or if it's virtual only existing in the GUI....Any insight or experience with this behavior?

NOTE: I have both Sentry & Cabin Overheat Protection DISABLED, my vehicle is either asleep or offline for the significant majority of the stay at work, and my recent "monitoring" is only keeping the vehicle awake for ~1 hour after arriving at work....

what's the temperature ?

 

[insaneoctane]

what's the temperature ?

It's been happening since temps were in the 70s. Most trips in my data are without AC or heater

 

[VT_EE]

I'm NOT seeing a net higher consumption from the wall in my initial analysis....

There is all kinds of weirdness going on with the BMS in all models running recent software builds. There are obviously bugs they are dealing with. Thanks for the info.

 

[insaneoctane]

So, I've added an algorithm to my data collection that runs for 60 minutes after I park at work and emails me the range vs time in 1 minute increments so I can monitor this behavior. It's not an awesome story. Losing 15 miles into the ether is something I hope is just a firmware bug....but until Tesla figures this out I'll keep my eye on it. Here's today's graph: