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Wiki Consolidated eMMC Thread (MCU repair) (Black Center Screen)

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MCU1 (yours might be an exception) has already reached the point where all the updates have made it "slower, and not all features work" and that's why the owners opt for the upgrade to MCU2.
There's "slower" and then there's "basically nonfunctional" which is where mine has gotten to. As an example of what I mean, I'm talking about "put car in reverse, wait two or three minutes for reverse cam to come on". There are many more examples, but this isn't the place for an exhaustive list. Anyway, a long back-and-forth with Tesla has led me to a few conclusions. First, they know they broke MCU1 sometime in the last year; based on comments in the service records it seems like the breakage I'm seeing may be related to the 64 GB "upgrade" done as part of the recall. Second, they don't care and won't make it right at their expense, service contract be damned. Third, they seem to be short of MCU2 replacement parts, there's a long wait for me to get an MCU2 even at my own expense. (Which may then explain point 2 -- it's a form of rationing.)

To the people repeating the Tesla Corporate party line about "do you expect your 2012 iPhone to function just like a new iPhone?" the answer is no, but this is a false equivalence. I would expect my 2012 iPhone to continue to make and receive telephone calls just as well as it ever did, and that's what my MCU1 isn't doing any more -- I just want the damn reverse cam to come on when I shift into reverse, it's a safety issue. I couldn't care less about playing video games while I'm parked.

Anyone who works in a tech company of any size and age knows this problem -- you have a fleet of older hardware in the field and customers with service contracts. You wish you didn't have to support it, but you do, so you either fork a maintenance code train for the older hardware and it only gets critical fixes, not memory-hungry new features, or you suck it up and give the customers new hardware at your expense so that you don't have to eat the overhead of maintaining multiple trains. There is no valid option 3, that they are trying to excuse this as "oh well this is just how things happen in tech" is cringeworthy.

ETA: what you definitely do not do is push an update and then say "oh ha ha we seem to have gone fast and broken things and in this case 'things' means your car, sucks to be you, pay me or GTFO."
 
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There's "slower" and then there's "basically nonfunctional" which is where mine has gotten to. As an example of what I mean, I'm talking about "put car in reverse, wait two or three minutes for reverse cam to come on". There are many more examples, but this isn't the place for an exhaustive list. Anyway, a long back-and-forth with Tesla has led me to a few conclusions. First, they know they broke MCU1 sometime in the last year; based on comments in the service records it seems like the breakage I'm seeing may be related to the 64 GB "upgrade" done as part of the recall. Second, they don't care and won't make it right at their expense, service contract be damned. Third, they seem to be short of MCU2 replacement parts, there's a long wait for me to get an MCU2 even at my own expense. (Which may then explain point 2 -- it's a form of rationing.)

To the people repeating the Tesla Corporate party line about "do you expect your 2012 iPhone to function just like a new iPhone?" the answer is no, but this is a false equivalence. I would expect my 2012 iPhone to continue to make and receive telephone calls just as well as it ever did, and that's what my MCU1 isn't doing any more -- I just want the damn reverse cam to come on when I shift into reverse, it's a safety issue. I couldn't care less about playing video games while I'm parked.

Anyone who works in a tech company of any size and age knows this problem -- you have a fleet of older hardware in the field and customers with service contracts. You wish you didn't have to support it, but you do, so you either fork a maintenance code train for the older hardware and it only gets critical fixes, not memory-hungry new features, or you suck it up and give the customers new hardware at your expense so that you don't have to eat the overhead of maintaining multiple trains. There is no valid option 3, that they are trying to excuse this as "oh well this is just how things happen in tech" is cringeworthy.

ETA: what you definitely do not do is push an update and then say "oh ha ha we seem to have gone fast and broken things and in this case 'things' means your car, sucks to be you, pay me or GTFO."

Agree 100%. I would be glad to go back and have the software my car had when I bought it in Feb 2015 (I believe it was version 7). Everything worked then but soon started to receive all these bloatware and get broken with each so-called update. My MCU1 is non-functional and I've been waiting to get the upgrade to MCU2 for over two months (they are still waiting for the parts).
 
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I agree with MCU1 being almost unusable in some cases. Sometimes the rear camera takes forever to appear, or it never does. Other times you get in the car and the system is rebooting for whatever reason, and you need to wait for a very loooong time until you have access to navigation. And these problems happen too often.

Nonetheless, there is NO WAY Tesla would fix this usability problem by installing the MCU2 in MCU1 cars. It still "works" (sort of), then it's enough.
 
And get this, navigation on, I reach the intersection and supposed to make left, no voice guidance, but familiar with that turn, make the turn, and a minute or so later the voice guidance tells me to make the left turn at the intersection which I've already past.
 
I'm running on 2021.24.28 (latest in the stable, non advanced/bleeding edge update stream) and it works fine for navigation and music streaming (and app connectivity to pre-heat/cool, etc). Maps can take a bit to load when adding a new route, but as the car is driving I never see blank tiles. Menus have become less responsive with each update, but still functional. I drive my wife's MCU2 from time to time, and honestly, while I see the difference in responsiveness, it's a non-issue for me. I more notice the acceleration difference and lack of sport+ suspension than the MCU difference.

Your comment made me think about how much would I be willing to pay for MCU2. I started with, what if Tesla offered to do it for free with FM radio. Hmm.... honestly, I'd probably do it just to increase the resale value. Then I thought, how about $100? Probably yes. $200, still yes. $300, ok. $400 - $500, maybe. Above $500, no desire whatsoever. Next year, when my Taycan CT Turbo will finally come to replace the Model S (have been waiting for almost a year now), I will inform the next owner they have the option to pay $1,500 or $2,000 for an updated MCU2 if they so desire (maybe they can get a credit for MCU1 recall since Tesla denied my claim after self-repair of emmc). Me spending the money now would not raise my used car value by the same amount, and since I don't see the value in functionality for me, there is no reason to spend the money.
I went to the service center earlier today to ask them why my 2017 Model S is still on 2021.24.28 and learned that it is the latest stable release on MCU1, which was the first I'd heard of MCU2.

They asked me to leave the car with them to do the eMMC upgrade and I see posts about glitches after this "upgrade" :(

I'm now looking at MCU1 vs MCU2 discussions and, like you, I have no interest in video streaming or gaming though a more responsive touchscreen would be nice. Losing radio would be mildly inconvenient.

Doesn't MCU2 also enable Sentry Mode video recording and playback, though? That might swing my decision in favor of the upgrade.
 
Can you create sentry mode footage on an AP1 vehicle with MCU2?
No. I assume you mean from just the front mobile eye camera? I don’t think Tesla could do that even if they wanted to because isn’t the processing of those images also done in a CPU in windshield camera unit?

Although it would be funny to see a hacked backup camera only sentry on AP1 MCU2.
 
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So got the car back with the larger eMMC. Good news is that there are no screen bubbles, middling but unsurprising news is that all profiles including WiFi, Bluetooth and HomeLink are gone and will have to re-created, disappointing news is that music streaming with the Premium Connectivity package is gone even though the car and the web account confirm that it still exists.

Also, default display in the right third of the front display in front of the steering wheel used to be tire pressure and is now battery consumption and I cannot for the life of me figure out how to get it back to the way it was.
 
Also, default display in the right third of the front display in front of the steering wheel used to be tire pressure and is now battery consumption and I cannot for the life of me figure out how to get it back to the way it was.
So pressing down on the right scroll does not bring up a scrollable window that you can select other options?
 
Wife would not want to see dangling wires and I don't know how hard it is to run the wires along the headliner and where to splice them in for power
I had mine installed by a professional at a place familiar with Teslas (even 7 years ago!) that does car stereos, radar detectors, etc. No dangling wires anywhere. Dashcam sits mostly in front of the rear view mirror
 
Wife would not want to see dangling wires and I don't know how hard it is to run the wires along the headliner and where to splice them in for power
No need to splice wires - just wind up the unused part and hide it under the headliner. You can shorten the power wire, but it is just wires, so no splicing. I installed 2CH BV dashcams in all four of out Model S now, even the one with MCU2 and sentry mode available since the dashcam is more reliable and draws significantly less power (therefore less vampire drain while parked). All our dashcams are powered from the unused 12V alarm under the microphone panel on the ceiling, and wire to the back goes under the headliner, through the rubber boot to the tailgate, then under the tailgate plastics. No wires dangle anywhere. Even the front dashcam itself is installed such that from the driver's position you cannot really see it as it's hidden behind the rear-view mirror.