Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Refreshed Model S Plaid MCU hard resets repeatedly during Supercharging

Not sure if anyone can confirm if the aforementioned update fixed the issues. I have a 22 MS LR (I know this is a plaid forum). Wanted to make this group aware that I’m experiencing almost of of these issues with my LR while super charging - both at 150 & 250 Kw stations (my horn also randomly goes off 1-2 times as well. I have an appointment on 1/17 to see what’s going on. Every time I have to hard reboot after charging to get the car back to normal.
 

JAS037

New Member
Dec 12, 2021
1
0
34986
Hi all,

Taking Model S Plaid in a road trip at 2021.36.8.9 (FSD 10.6). During 5 Supercharging sessions, 4 repeatedly reboots after SoC.
In out of 5 Supercharging the Model S Plaid for 1000 miles road trip, 4 of the following sessions failed
  1. 71%-86% (15kW)
  2. 14%-96% (82kW)
  3. 17%-70% (50kW)
  4. 10%-60% (49kW)
Observed issues
  1. MCU reboots continuously without stopping. GUI displays for few seconds and is responsive before each reset.
  2. No errors displayed during the reboots, with the two following single occurances (unsure if they're errors from being reset)
    1. "Cruise control unavailable"
    2. A sizzling icon that indicates something is overheating. I didn't have chance to read it before display resets
  3. Usually before reboot, I can hear high pitch pump ramping up. It sounds like the battery cooling system.
  4. During reboot, air conditioner shuts off along with MCU
  5. To stop the cyclic reboots, Supercharger needs to be unplugged. After unplugging, MCU typically reboots several times before stabilizing.
  6. Sometimes after reboot, the following turns off
    1. Navigate on Autopilot
    2. Traffic Light Chime
    3. Sentry mode
No reboot in the 5th session, from 10%-74% (64kW)
Following settings were set in attempt to debug
  1. Navigate on Autopilot and traffic light chime were disabled. They were disabled due to previous MCU resets by Supercharging
  2. AC was turned off manually

Questions
  1. During the return trip, I will be keeping notes of the Supercharging behaviors. What settings should be tested and noted? I should have 6 sessions of Supercharging, charging from 10%.
  2. Is this a software issue, or a MCU hardware/battery hardware issue?
I would set up service ASAP at Tesla. Mine has problems at superchargers too, but not like yours!
 
Update from Tesla:
IMG_20220104_142150.jpg


As I suspected, no obvious hardware issues. That's not to say that it still could not be a hardware related issue that's hard to detect with whatever data they have available.

But I did my part for now, so hopefully they got some useful data from it.

If you're having this issue make sure to setup a service appointment so they can pull logs as well.

The more data and cars with this issue they get, the more likely they are to find a fix (albeit hardware or software).
 
Update from Tesla:
View attachment 751937

As I suspected, no obvious hardware issues. That's not to say that it still could not be a hardware related issue that's hard to detect with whatever data they have available.

But I did my part for now, so hopefully they got some useful data from it.

If you're having this issue make sure to setup a service appointment so they can pull logs as well.

The more data and cars with this issue they get, the more likely they are to find a fix (albeit hardware or software).

Did they request a specific date time of the event? The SC team here requested timestamp, I assume for them to study the log files for repeated resets.

I am suspicious of just relying on self-reported diagnosis, since forced hard reset may not allow the software to explicitly log the issues prior to crashing.
 
Did they request a specific date time of the event? The SC team here requested timestamp, I assume for them to study the log files for repeated resets.

I am suspicious of just relying on self-reported diagnosis, since forced hard reset may not allow the software to explicitly log the issues prior to crashing.
I experienced pretty much all of the errors [you] described above.
Just got the car back from service. They replaced the “Car Computer” as well as a “thermal unit” (fortunately, my car reproduced all of the errors for the service team when they charged it).
Service Team doesn’t know why some are failing so they shipped the old computer back to Fremont engineering to diagnose. Good news… it drives so much better - smoother. Bad news is ALL personal settings were erased - had to spend about 15 min in the parking lot to reprogram (worth it). Hope this helps and good luck with your fix. I’d recommend your service center call mine (Jacksonville, FL) if they’re stumped.
 
I have had one Supercharger session where the MCU was doing back to back reboots about five times. I terminated the session, waited a bit and then did a two thumb reboot and all was normal. I suspect per others that the MCU is overworked during Supercharging as I bet the batter condition monitoring takes a ton of CPUs and likely experiences a memory leak.
 
  • Like
Reactions: electrongofast
I'm glad I found this thread.

Started Supercharging my plaid today for the first time for my first road trip and here's what happens to me (2021 plaid running 44.6):

During SuperCharging:

Cameras slowly freeze up and become unresponsive or render about 5 frames a minute.

Internet Drops (WiFi still works tho).

If I have a trip set, it flashes between ready to continue trip and X minutes remain to continue trip

Tire Pressure which usually shows "--PSI" when setting still disappears completely for a moment then returns .. repeatedly (not sure if related).

The outside temp in the driver cluster switches to "--F" then shows temp, and switches back and forth... Repeatedly.

The rest of the interface is still smooth and responsive.

When Supercharging finished:

FSD visualization preview is slow and jumpy.
TPMS and Parking Brake lights flicker on and off as well as "Assisted Parking Unavailable"

Cameras still don't work or only render a few frames a minute.

Rest of the interface still smooth and responsive.

Resetting the system (via steering wheel) does not fix the problem immediately unless you wait a few moments after charging.

So steps to clear:

Wait a few moments after charging.
Force reboot via steering wheel.

Then all is normal. Smooth. Like it never happened.


This does not happen when charging at home. Only Superchargers cause it.

I'm glad I'm not the only one with these issues.

My 17 years of software experience senses are tingling that this is a memory leak or general issue with system resource allocation.

But I'm not a Tesla expert, so it could very well be something else.
Same here. Did Tesla service able To fix it? What was the cause for this malfunction?
 

sorka

Well-Known Member
Feb 28, 2015
9,519
7,827
Merced, CA
Service center confirmed that this is a firmware bug, and is resolved in 2021.44, which is unavailable for me just yet. @iandkirby looks like you are still having weird issues in 2021.44.5 though

Their telling multiple Refresh X owners this is just a firmware bug, and then they update the firmware and the problem persists.

Is anyone NOT having this problem when supercharging their refresh? Seems to be rampant on the refresh X:

Multiple reports in this thread:
 
22 Plaid Feb build, 1500 miles and i just did road trip this past weekend. 3 supercharging sessions.

1. Seems to be normal except the AC fan went to max, but was able to charge from 30% to 85% with no issues. I was using Disney and we did not see any reboots. Station was 250kw but was throttled down to 150k due to high usage

2. Next day same SC when my car went crazy with the multiple reboots. I was charging from 40% hoping to get it to 90% so i can get home without charging again. I had to stop the session at 60%. No errors on screen. After this i noticed my backup camera was black so i did reset the MCU (no brake) and camera came back online.

3. last session was at another 250kw SC. No issues at all from 30% to 80%. I did set the fan manualy not Auto and i did not notice any issues and AC fan did not kicknto max.

This is very concerning, what if the car stuck and i could not disconnect the SC cable and gets charged idle fees for god knows how long. Any ideas? This is my first Tesla.

I have my 1 st appointment with Tesla in 2 weeks (fingers crossed they wont reschedule again) so I added it to the list of items to report🤞🏻🤞🏻
 

Products we're discussing on TMC...

About Us

Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.

Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


SUPPORT TMC
Top