MCU failures

waynecheung.waynecheung_98189434 · January 11

There have been incidents that the MCU does not power on, like for 5 mins and still a no-power blackscreen, sound lost (streaming, radio, signaling), and sudden signal drop (4 bars to suddenly no connectivity at the same spot) and would require a soft reset (holding both scroll wheels) to resolve. May be not affecting driving but I cannot access the MCU to open the garage too :(. I scheduled for an appointment for that MCU emmc check and replacement but the appointment got cancelled without my confirmation. Tesla service left a message saying they have done a remote analysis, 2 weeks after the previous incident, and claimed it was working at that time (of coz it would, else I won't be able to open my garage for a while) and said they have therefore cancelled my appointment.
I would like to confirm if these signs/incidents more due to the emmc chip failure on the MCU? My model X is the Oct 2017 model. I have book another appointment again about this issue since MCU just failed to start again few days ago and hoping they don't cancel again.

timleynes · January 14

I have driven my model X only for 356 miles...

Today my screen went black, not able to signal and the front dashboard "screen went black" too. I was about to pull over to a safer location, then the power came back on and continue to drive home.

This would have been very scary if it happened at night and lost the headlight.

I have reported my problem using my mobile and got a scheduled mobile dispatch to my place on Friday, Jan. 15th, 2021.

Redmiata98_93075535 · January 17

If you are still under warranty, there is a “warranty adjustment program” that covers this. There is also a NHTSA request for a recall on this.

TeslaTap.com · January 17

@timleynes - How new is your car? For 356 miles, it sounds like a 2020 or 2021 model X? @Redmiata's advice doesn't apply to newer cars. It was an issue for those made before March 2018 that have MCU1.

The screen going "black" was a reset. Is there any chance you pressed both scroll wheels in at the same time? That is one way to force a reset. There may be something else going wrong which service can take a look at the logs. Note that the car does not need the MCU to drive. If your headlights were on, they would have remained on. Still, it can be disconcerting to not see the speed and other functions.

Redmiata98_93075535 · January 18

The first poster has a 2017, the program applies to those manufactured prior to March 2018.

Redmiata98_93075535 · January 18

Go to the Tesla web page under Support and Warranty Adjustment Program.

Redmiata98_93075535 · January 19

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwj18vjzy6TuAhWjzlkKHUbFA_IQFjAAegQIBhAC&url=https%3A%2F%2Fwww.tesla.com%2Fsupport%2Fwarranty-adjustment-program&usg=AOvVaw0H0JX8EPtrsoVt6OLPEdDm

Ruingate24 · January 19

So my 2017 that I got in Dec has had the MCU freak out a few times and now has frozen up on me while driving. Its a bit disconcerting. I took it in for a service appointment. Also I have the older MCU, and was told If I wanted the careoke one I'd have to pay full price for it. So I guess they are attempting repair or replacement with the older MCU. Still waiting on results though.

Redmiata98_93075535 · January 20

Tesla has until 27 Jan 21 to reply to NHTSA 13 Jan 21 letter asking for a reply on the inquiry on the longevity if the NVIDIA Tegra 3 processor with an integrated 8GB eMMC NAND flash memory device. Tesla’s current Warranty Adjustment only commits to “repair or replace” the same 8GB part when it fails. NHTSA projects the lifetime of the part @5-6 years. My fingers are crossed that Tesla does a recall and replaces the part with the larger memory module rather than just repair.

timleynes · January 22

> @"TeslaTap.com" said:
> @timleynes - How new is your car? For 356 miles, it sounds like a 2020 or 2021 model X? @Redmiata's advice doesn't apply to newer cars. It was an issue for those made before March 2018 that have MCU1.
>
> The screen going "black" was a reset. Is there any chance you pressed both scroll wheels in at the same time? That is one way to force a reset. There may be something else going wrong which service can take a look at the logs. Note that the car does not need the MCU to drive. If your headlights were on, they would have remained on. Still, it can be disconcerting to not see the speed and other functions.

My car is a 2021 model X and i got it 2nd week of Dec. 2020. The screen went black while I was driving and I kind of "panic" and not knowing what to do, I pressed the scroll wheels in at the same time even not knowing it will reset the screen. And it did reset and the screen showed it was restarting. then it came stayed on.

I took my car to the Tesla Service and they confirmed the issue. They did a diagnosis and found formatting error with the internal SD card. It was reformatted successfully and updated to firmware version 2020.48.30. I have driven about 50 miles and so far so good. Hopefully, and keeping my fingers crossed that this will not happen again...

timleynes · January 22

Forgot to mention that it was serviced under warranty. They gave me a loaner Tesla model S. Did not pay for anything. Thank you!

TeslaTap.com · January 22

@timleynes - Glad they sorted it out for you!

ECX100 · January 24

> @"waynecheung.waynecheung_98189434" said:
> There have been incidents that the MCU does not power on, like for 5 mins and still a no-power blackscreen, sound lost (streaming, radio, signaling), and sudden signal drop (4 bars to suddenly no connectivity at the same spot) and would require a soft reset (holding both scroll wheels) to resolve. May be not affecting driving but I cannot access the MCU to open the garage too :(. I scheduled for an appointment for that MCU emmc check and replacement but the appointment got cancelled without my confirmation. Tesla service left a message saying they have done a remote analysis, 2 weeks after the previous incident, and claimed it was working at that time (of coz it would, else I won't be able to open my garage for a while) and said they have therefore cancelled my appointment.
> I would like to confirm if these signs/incidents more due to the emmc chip failure on the MCU? My model X is the Oct 2017 model. I have book another appointment again about this issue since MCU just failed to start again few days ago and hoping they don't cancel again.

ECX100 · January 24

Tesla says Model X is drivable without the center panel. Can’t turn on heat or defroster, and in cold weather windshiekd fogs up. That is not drivable..Lots of other safety, drivability and conveniece issues when MCU fails. No ETA on fix. Tesla says it is a firmware bug. Why isn’t this the #1 priority? Its been getting progressively worse for months. I don’t need another update with an 80’s arcade game. I need a defroster, heat, a backup cam, and all the other controls the center panel provides with no alternate controls.

barskidc_98661254 · January 26

I won't belabor the details which are amply outlined in numerous articles, forums, complaints. Whether your concern is safety, disappointment, or disgust, Tesla as chosen to abuse the customer experience of loyal customers to hide, delay, or save a buck. I have lost hope that Tesla will do the right thing by their customers regarding touchscreen performance, blackouts, reboots and potential safety issues. I have had my 2017 Model X 90D in 3 times for this and get the same excuses about why their cars are poor in performance. I am afraid that they must be forced to address it along with a fear that it will affect their financials. It appears they are using 2 cleaver approaches to mitigate their exposure: 1) doing a recall only when the chipset fails after customers have suffered for months or even years with poor performance, and 2) enticing customers to pay to upgrade their way out of the problem and potentially profit from the quality defect. I have been a Quality Management professional for most of my career and it is often arrogance and success that clouds the perspective of Executives who tend to forget who pays the bills. I purchased my first Tesla knowing there would be problems - all products have some problems; I just believed that Tesla would take better care of their customers - time will tell...

TeslaTap.com · January 26

@ECX100 - If your car is not drivable, have it towed to service for repair. Most find if the MCU fails, you can drive the car, but you have to be aware of some non-essential things not working. It doesn't mean it will be comfortable.
It doesn't sound like yours has failed, but it intermittent? Most are not that worried about driving it to service at that point, but clearly, you feel it is not safe, so have it towed. I don't know if Tesla will cover the towing costs for that situation.

There is no firmware fix. Your choices are a new daughter board (free if in warranty) or pay for an MCU2 retrofit. One problem is there is a backlog on getting the daughterboard, as the daughterboard manufacturer went out of production years ago, so they only have a small stock left that they rotate and repair with the better part.

ECX100 · January 27

Thanks for the thoughtful detailed reply. I am glad to know about your site. A wonderful amount of much needed detail. With my center planner issue, Tesla has changed the story a number of times. In November, after increasing and lengthier reboots they cleared the cache remotely. No help. They then said I needed a new MCU board, ordered it and scheduled installation January 4. They kept the car for a week, when I picked it up panel was still frozen. They said the logs showed no faults so they did not install the new MCU they had, They said it needed a hard reset and needed to send a mobile tech to do that, A week later he said that would not do any good so did not do it. He said it is a known firmware bug unresolved since release 34. I am on 2020.48.12.1. He said it manifests itself with the same symptoms as the EEPROM failure. He said I needed to wait for new firmware download, No ETA, As I approached the end of standard 50K warranty, I wanted to be sure it was a know problem still covered. Tesla no says it is a corrupt file they will try to repair remotely. A new consequence of the MCU failure is that AC and radio stay on and car looses 15 miles per day while parked in garage. Long term experience (3 1/2 years) is that the car never loses more than a few miles per day in park, even if outside in colder weather ( I am in the Northeast US so occasional sub-freezing).

ECX100 · January 27

Further progress, it appears that a corrupted file was the culprit, not the MCU hardware. Tesla remotely identified and replaced the file and the center panel and voice commands operated normally for the first time in 4 months. Very responsive vs. frozen or very slow responses. One other thing, they asked me to (at least temporarily remove the Tesla recommended USB drive used for Sentry mode.

TeslaTap.com · January 27

@ECX100 - Thanks for coming back and explaining the solution. Nice that they could fix it remotely.

polar_bear · January 28

I have a 2016 which we got about 1.5 years ago as pre-owned through Tesla. started getting corrupted screen, freezes and slow reboots about 6 months ago. Does not happen very often - but often enough to be annoying: it usually garbles in backup camera mode - and our driveway is sloped and has turns.
I managed to take some photos of garbled screen and took it to Tesla service center. Was told the issue is not related to EEPROM and to wait for an update.
Service engineer suggested a reboot and pushed the 2 buttons - but refused to wait with me for reboot to complete - because it takes too long. Well, his time is valuable...
Yesterday was the deadline for Tesla to respond to the recall request. Can not find anything in the news.

timleynes · February 19

> @"TeslaTap.com" said:
> @timleynes - How new is your car? For 356 miles, it sounds like a 2020 or 2021 model X? @Redmiata's advice doesn't apply to newer cars. It was an issue for those made before March 2018 that have MCU1.
>
> The screen going "black" was a reset. Is there any chance you pressed both scroll wheels in at the same time? That is one way to force a reset. There may be something else going wrong which service can take a look at the logs. Note that the car does not need the MCU to drive. If your headlights were on, they would have remained on. Still, it can be disconcerting to not see the speed and other functions.

The screen black out happened again...
Here is the message from Tesla Service Center after my 2nd screen blackout on Feb. 12th, 2021:
"Our diagnostic team has performed some checks and pulled data logs from the timestamp you have provided. We see here that you use your web browser on your Model X. There are some websites that use cookies and websites aimed at accessing vehicle data or apps which causes your system logs in your MCU to keep pinging request even when you are not on or using the web browser. This can cause the MCU to overload on request from the vehicle computer to make your processor overload and reboot. I would suggest to stay away from certain website when using your Media control unit. If the touchscreen keeps rebooting i would suggest a factory reset to alleviate the rebooting if it becomes consistent."

I was told to avoid using the CNN or MSNBC. I replied that it appears like the tune-in to CNN or MSNBC flooding the memory seem to be a system functional issue...

I requested them to confirm that the rebooting of the screen is NOT going to impact the headlights, tail lights and hazard lights since I did not feel comfortable rebooting the screen while driving...

Below is the confirmation i got from the manager.

"Great news Tim, I have gotten confirmation from our Engineers that the headlight should not be affected by the MCU and IC reboots. Operations like lighting etc should not be effected as the headlights are powered separate from the computer."

I replied and said i will avoid to use the CNN or MSNBC. And I was told to do a "bug report" the next time it happens again. I am keeping my fingers crossed that this MCU issue/rebooting for the screen will not happen again if I do not tune-in to CNN or MSNB... will wait and see.

packpike · February 26

@ECX100 How was the corrupted file found? My wife drives our 2017 MX and has been reporting similar issues to the OP. I mentioned it to our mobile service guy while he was out doing some work on my M3 and he said that they would look into it. We had the MCU replaced ~1 year ago because it failed and he remotely confirmed that the memory is healthy and that there were no other hardware faults. My wife is now going to log when the issues happen for them to look deeper.

Hugh-SG · March 6

As everyone should by now be aware, there is a Recall now in progress for the cars with 8gig chip in their MCU1's to be upgraded to a daughter board with 64 gig chips, so I will not go into detail on that.
I visited the Vancouver (BC) SC, last fall (late 2020) for a reformat and full reload of software to help make the problem "livable" until the 8 gig chip suffered total failure.
I was told by the SC that they would not replace the daughter board with a 64gig chip daughter board until the 8gig chip completely failed.
Fellow Tesla Club of BC members have advised me to do a "bug report" every time I experienced any problem with an immediate follow up call to Vehicle Support, so that they could make a record of the problem and would be able to download the vehicle log remotely to let the engineers look at what had gone wrong.
IF this happens on the Weekend I was advised (again by fellow TMC-BC members), that when Vehicle Support is closed, do a nice polite call to the Emergency Line, asking them to please note on your file that the "bug report" was done because of (name of problem) and would they be so kind as to note it on your vehicle log, so Support can do a follow up.
BTW, my center console suffered Black Screen death yesterday (March 5th, 2021) just after I unplugged from Supercharging. I was able to do a scroll wheel reboot but did a "bug report" and follow up call to document my MCU1 suffering a Black Screen death.
Hopefully the good folks at Vancouver's (BC) SC will be getting in a supply of 64gig daughter boards soon. Everything from the Tune-In to the Navigate - Map now seems to be taking forever to load and do their functions.

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MCU failures

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