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Preventive eMMC replacement on MCU1

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widodh

Model S 100D and Y LR
Moderator
Jan 23, 2011
6,861
2,840
Venlo, NL
Many stories out there tell that the flash storage (eMMC) on MCU1 will wear out sooner or later. This is known with flash memory and at that moment your Tesla will die. It won't charge and possibly only drive in limb-mode.

I have a 2013 S85 and a 2018 100D and the first one still has an MCU1 which has been running for 5,5 years now.

If the MCU dies Tesla will charge EUR 3000 (I'm in Europe) for a MCU replacement while only a small memory chip has failed.

I found this blog: Replacing eMMC in MCU

The same is shown in this video:

I've just ordered 64GB of eMMC storage for ~EUR 80 and a AllSocket eMMC programmer so that I can re-program the memory.

I'll go to a local electronics repair shop to help me with de-soldering and soldering the eMMC on the MCU. I'm thinking about doing this preventive to make sure the car doesn't die on me while driving. It's not a question of "if", but "when" it seems.

Has anybody replaced the eMMC memory on their MCU1 and can share some more experiences?
 
I like to see where this is going... :cool:
So am I :) Waiting for:

- Flash to be delivered ( 64GB Swissbit EM-20 Series Industrial eMMC Memory )
- AllSocket programmer ( ALLSOCKET BGA169 BGA153 Socket eMMC169/153 )

Then, the steps:

- Power off the MCU (pull the proper fuse(s))
- Remove the MCU
- Remove the card which holds the eMMC
- De-solder the eMMC
- Place the eMMC in the AllSocket programmer
- Using Linux dd create an image of the Flash storage
- Program the new flash storage
- Solder the eMMC on the board
- Connect the MCU
- Power on the MCU
 
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I'm considering the same. My MCU crashed a few weeks ago when I tried to switch language. It never came back from a reboot, screen stayed black no matter what I (and Tesla phone support) tried. Car was driveable but no air/heat/music/connectivity, and CID was in miles/h instead of km/h. Took it to service, they had to reinstall firmware twice and then it was back alive. Safe to assume my emmc is starting to corrupt and needs to be replaced before it fails completely.

I'm in the process of sourcing the chip/reader and reading about how to remove the dash&mcu, found this tut:
Fix.My.EV: Tesla Model-S Repair Manual
(although I'm not sure the complete top of the dash needs to be unclipped and removed, just loosen the part above the mcu should be enough)

I can also point you to an experienced technician who can replace the emmc bga for you, he actually lives close to you so you might contact him, his name is Dennis his details are on www.allsystemsgo.nl. (say hi from me if you contact him!) he does all kinds of crazy expert repair work on phones, tablets, laptops etc.
 
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I have a 2013 S85 and a 2018 100D and the first one still has an MCU1 which has been running for 5,5 years now.
...
As your 2013 Model S is already out of warranty, would you (and others) consider disabling the superfluous error logging on the eMMC card altogether?

I've had Phil remotely root my car in 2017 and do some software repairs on the sat nav. Can recommend him. My eMMC logging was disabled at the time. A few months later Tesla switched out the MCU to repair non-functioning Bluetooth. :(

Now I'm considering rooting it again. If others are interested, send me a PM.
 
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Reactions: .jg.
As your 2013 Model S is already out of warranty, would you (and others) consider disabling the superfluous error logging on the eMMC card altogether?

I've had Phil remotely root my car in 2017 and do some software repairs on the sat nav. Can recommend him. My eMMC logging was disabled at the time. A few months later Tesla switched out the MCU to repair non-functioning Bluetooth. :(

Now I'm considering rooting it again. If others are interested, send me a PM.
It's out of warranty indeed. I can disable logging, but I fear that after 5,5 years and 250.000km on the ODO the eMMC is nearing it's end.

I'd rather replace it then hope it doesn't wear out.

Thing to add: My wife drives this car mainly and I don't want her to be stuck somewhere with a car due to a broken eMMC chip.
 
I just put a down payment on a 2014 Model S P85 and this has been the thing I can't stop thinking about since it seems to be a matter of when, not if it fails. I'm open to suggestions for a long term preventative solution.
From what I've seen and read it seems like this is indeed a "when" and that the only thing that helps is replacing the eMMC with newer eMMC which lasts longer.

Tesla should update their firmware so that they don't write that much data.

But if your eMMC is still OK it might last another year, maybe two depending on your car's usage. But it will wear out at some point.
 
But can't this replacement be done only when the original eMMC dies for good?
No. If you 'Power Off' the car, then kill the 12V you can take off the eMMC of the MCU.

Now you can bitcopy the eMMC using a Linux computer and then put the new eMMC back on the MCU.

Afterwards you connect all the wires and boot the MCU. Nothing has changed and the car still works.
 
No. If you 'Power Off' the car, then kill the 12V you can take off the eMMC of the MCU.

Now you can bitcopy the eMMC using a Linux computer and then put the new eMMC back on the MCU.

Afterwards you connect all the wires and boot the MCU. Nothing has changed and the car still works.

Hmmmm.... that sucks...
If that is the case, then Tesla should man up and offer it's customers a solution to prevent the total colapse of the original eMMC (maybe changing the eMMC themselves).
Does this affect all MCU's or only MCU 1?
 
Hmmmm.... that sucks...
If that is the case, then Tesla should man up and offer it's customers a solution to prevent the total colapse of the original eMMC (maybe changing the eMMC themselves).
Does this affect all MCU's or only MCU 1?
If Tesla should cover this is a different discussion.

This seems to affect MCU1 only, but we can't say for sure since MCU2 has only been out for about 1 year now.

But in the end all NAND will wear out after writing to it for a long period.
 
No. If you 'Power Off' the car, then kill the 12V you can take off the eMMC of the MCU.

Now you can bitcopy the eMMC using a Linux computer and then put the new eMMC back on the MCU.

Afterwards you connect all the wires and boot the MCU. Nothing has changed and the car still works.

Any idea of any places on the East coast of the United States that can do this? I definitely wouldn't attempt this myself.
 
I too am interested. in East Coast. If I can get the equipment, I would try to do it. need someone to coach me. Heavy into computers and design for over 40 years.
Any idea of any places on the East coast of the United States that can do this? I definitely wouldn't attempt this myself.
I think the guys from Rich Rebuilds in Boston can do this.

I'm in Europe, so there is a big pool of water in between :) I'm sourcing the parts and proper tools locally right now and will attempt this replacement later this summer.
 
Hi! Happened to mine S here in Norway, 4 years old and 235k km. Replacing yourself the eMMC is not easy at all and bears the risk to damage more than it is. Tesla checked the logs (online) and told me it happened during FW update. Probably that's the reason replacement was a goodwill from Tesla :) A great service! Yes, can be a big issue in a cold winter.