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Refreshed Model S Plaid MCU hard resets repeatedly during Supercharging

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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?
 
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I would suggesting looking through the notification logs in the MCU. Perhaps you could ask Tesla Service Center to check the data logs to see if something is seriously wrong where you shouldn't be driving the car until it's corrected. I'd also recommend you take a video of what's happening so you will have some evidence. Like in any car, sometimes the technicians cannot replicate the issue when you bring them your car.
 
Notification had no errors. Did record video, will share with SC. Just saw an old thread with the same problem for refreshed S

 
I have a plaid and have seen similar behavior when supercharging (seems to happen at 250 kWh chargers more consistently than 150 kWh ones), but there are some key differences in my experience too.

- I haven't noticed any sizzling icon
- I haven't noticed any noises foreshadowing the reboot
- The reboots are infrequent and only happen once or possibly twice in a single session
- The configuration has not reset itself
- The symptoms seem correlated to interacting with the front-center display
  • Today it happened while playing a Twitch video
  • The first time it happened, I was playing an arcade game, though I don't recall which - notably this was an occurrence where I reproduced the error by reopening the game after the reboot.
  • Another time, it was using the built in browser and Android-Auto
My general feeling on it (completely speculation and not founded in any significant observation) is that the computer must be limiting available resources while supercharging, such that once those resources are overutilized, it causes a system crash. I checked my phone today to see if the connection over bluetooth was still active while the reboot was in progress and it showed it wasn't connected.

I don't know if that helps or just adds confusion to the OP's explanation, hopefully the former.
 
Had this same behaviour (roughly) yesterday. Mine even went crazy saying it was in Dyno mode. Gearbox fluid service etc etc etc. Best Tesla crash I've ever seen. They pushed me 2021.44.5 today and it was better, although the map was dead after and it said my emergency brake was on while driving along with low tire pressure....oh tesla.... reset fixed.
 
I have a plaid and have seen similar behavior when supercharging (seems to happen at 250 kWh chargers more consistently than 150 kWh ones), but there are some key differences in my experience too.

- I haven't noticed any sizzling icon
- I haven't noticed any noises foreshadowing the reboot
- The reboots are infrequent and only happen once or possibly twice in a single session
- The configuration has not reset itself
- The symptoms seem correlated to interacting with the front-center display
  • Today it happened while playing a Twitch video
  • The first time it happened, I was playing an arcade game, though I don't recall which - notably this was an occurrence where I reproduced the error by reopening the game after the reboot.
  • Another time, it was using the built in browser and Android-Auto
My general feeling on it (completely speculation and not founded in any significant observation) is that the computer must be limiting available resources while supercharging, such that once those resources are overutilized, it causes a system crash. I checked my phone today to see if the connection over bluetooth was still active while the reboot was in progress and it showed it wasn't connected.

I don't know if that helps or just adds confusion to the OP's explanation, hopefully the former.
I agree with your assessment. It feels like a computer crash when it's out of memory. I suspect some computation regarding charging, since the continuous crash doesn't stop until charging is stopped? My 3 and S MCU both crashed once or twice during charging with heavy use, but I never noticed continuous crashing like this.
Had this same behaviour (roughly) yesterday. Mine even went crazy saying it was in Dyno mode. Gearbox fluid service etc etc etc. Best Tesla crash I've ever seen. They pushed me 2021.44.5 today and it was better, although the map was dead after and it said my emergency brake was on while driving along with low tire pressure....oh tesla.... reset fixed.
This explains the two erratic error messages that I saw.
- You mentioned 2021.44.5 was better, did it still have the same problem?
- Was your crash continuous?
Just got 2021.36.8.10, will find out soon if I still have this problem
 
Same issue here.
Plaid on 2021.40.6

Like others have mentioned it seems like the MCU is getting “overworked” while charging.
Everything seems fine then after about 20mins the system restarts and goes into a loop of rebooting and crashing. All kinds of warning signs flash on screen and sometimes the horn honks.

I have an appointment next week
for service, I’ll keep you guys updated with the results.
 
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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.
 
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.
That's not encouraging, I was told by tech that 2021.44 would fix this bug. I'm on 2021.36.8.10, so I couldn't test it out yet.