We shouldn't have to resort to "hacks" like these to keep our cars working as intended... With that said, most of those are reasonable advice given the piss poor software design on recent firmwares for MCU1 and will improve MCU performance. The one that is (mostly) complete BS is 1)... Missing firmware updates won't "overload the memory". New updates do provide an opportunity to create a new "clean" squashfs with the updated firmware on the emmc, which in turn might temporally breath new life into a failing part. But again, it's a bandaid at best and not a solution...
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We shouldn't have to resort to "hacks" like these to keep our cars working as intended... With that said, most of those are reasonable advice given the piss poor software design on recent firmwares for MCU1 and will improve MCU performance. The one that is (mostly) complete BS is 1)... Missing firmware updates won't "overload the memory". New updates do provide an opportunity to create a new "clean" squashfs with the updated firmware on the emmc, which in turn might temporally breath new life into a failing part. But again, it's a bandaid at best and not a solution...
Yes, you just change the memory chip in 3rd party repair shop and do a service request for Tesla to install the software and the certs if the certs were not able to be restored on the 3rd party repair.
In my case, I have a working MCU (the software was written to the new chip) but without the certs so I can drive the car to the Tesla SvC. My appointment is within 2 weeks so then I know more.
Actually the repeated attempts of OS loading could have rendered the eMMC unreadable. The software was a bit old, and recently push Tesla has for new software probably was a large cause of the certs not being recoverable.
Reminder for people that best time to get upgraded is before failure.
Most the suggestions are inline with minimizing writes. And I agree the system could have handled things better, and should not need owners to maintain it at those levels.
BigNick
Infamous Fat Sweaty Guy
This is proof that the original MCU1 was not built robust enough if a user has to do all this crap just to keep it working.
gasmiser1
Member
——————To add my info if it helps. Bought a used 2016 90D with 54k miles last Thursday. I started having issues with music skipping and no connectivity soon after. The service center on Monday and MCU has to be replaced. The total was $1300 for the MCU, $155 labor, $77 diagnostics and rest tax. Ended up being $1630 or so. Great way to start with a new to me car.
Mine gets replaced tomorrow at Tesla, new MCU1 16 gig chip.
Attachments
What makes you think that it is a 16 gig chip? I thought all MCU1s from Tesla only came with an 8 gig chip.
whitex
Well-Known Member
I just wanted to share with the community some advice after replacing my MCU1 emmc chip on a 2015 MS.
I knew my EMMC started to have issues, but was fooled by it not getting worse as long as I was not updating, and procrastinated for few months. Once I removed the emmc, it turned out the image was too corrupt to just do a simple transfer (luckily the car specific files survived intact). After 5 EMMC transplants later with some help from a kind samaritan with an image backup I could use to reconstruct the damaged parts of my emmc image, I now have an MCU1 faster than new and which will last 28 times as long as the original (7x P/E cycles * 4 times the size therefore available cells). Slight overkill? Maybe, but having 140 projected years (28 times as long as mine lasted), means that the performance degradation of emmc in the next 14 years will be the same my car saw over the first 6 months of its life. So, pretty much for the conceivable remainder of this Model S life, its MCU should continue to be fast and responsive unless of course Tesla software engineers screw it up by adding code bloat (new fart modes) or moving to some new abstract web technologies which overwhelm the CPU or memory capabilities in exchange for being able to hire cheaper developers. Also, should I choose to drive more or in hotter or colder conditions, emmc will age faster. Oh, besides the MCU being noticeably more responsive, my browser seems to be working, first time in many, many, months (maybe over a year, since v9 IIRC), except now only full screen, so not as useful for Tesla Waze and GPS map at the same time !
Some advice to share (things I did not see in some other howtos, or specific issues I happen to run into):
I knew my EMMC started to have issues, but was fooled by it not getting worse as long as I was not updating, and procrastinated for few months. Once I removed the emmc, it turned out the image was too corrupt to just do a simple transfer (luckily the car specific files survived intact). After 5 EMMC transplants later with some help from a kind samaritan with an image backup I could use to reconstruct the damaged parts of my emmc image, I now have an MCU1 faster than new and which will last 28 times as long as the original (7x P/E cycles * 4 times the size therefore available cells).
Slight overkill? Maybe, but having 140 projected years (28 times as long as mine lasted), means that the performance degradation of emmc in the next 14 years will be the same my car saw over the first 6 months of its life. So, pretty much for the conceivable remainder of this Model S life, its MCU should continue to be fast and responsive unless of course Tesla software engineers screw it up by adding code bloat (new fart modes) or moving to some new abstract web technologies which overwhelm the CPU or memory capabilities in exchange for being able to hire cheaper developers. Also, should I choose to drive more or in hotter or colder conditions, emmc will age faster. Oh, besides the MCU being noticeably more responsive, my browser seems to be working, first time in many, many, months (maybe over a year, since v9 IIRC), except now only full screen, so not as useful for Tesla Waze and GPS map at the same time !Some advice to share (things I did not see in some other howtos, or specific issues I happen to run into):
- Do not postpone your preventative EMMC replacement until it’s too late. I barely managed to recover car specific files due to my procrastination. I was slightly fooled by the fact that the MCU stopped getting worse when I started refusing updates and stopped streaming.
- With MCU out the DC-to-DC converter is not going to kick in to replenish the 12V battery, so a battery tender is a good idea if you are not disconnecting the 12V and HV batteries. HOWEVER, I found that if the car decides to run battery coolant pumps 24 hr a day, it will overwhelm even a 10 Amp battery tender and your 12V battery will be drained (happened to me twice in 7 days, as I was working on this only in the evening only, but with the COVID-19 it's not like I had anywhere to drive).
- Make sure you fsck check all your partitions, AND , and this is important (had I known this, it would have saved me A LOT of work) make sure you can unsquashfs partitions 1 and 2. If you cannot, no point soldering on a new EMMC chip, the MCU will not boot all the way.
- If you want best performance and longest life either reconfigure your new emmc to be 100% pSLC mode (cannot be done using the USB reader, only the SD one connected to an MMC controller - use "mmc enh_area set" command, WARNING, this is a one time operation, unreversible, so read up a little on how to use it), or buy it pre-configured from the factory as with the EM-26 series of Swissbit (which is just EM-20 series factory configured as pSLC). You get 7x the number or program-erase cycles, greater reliability, and faster I/O (read/write) performance over MLC mode – the only tradeoff is you pay twice the price for the chip since pSLC uses twice the cells for the same capacity (but given the effort to change it out, it was well worth the extra $35 to me). I got it to work with 32GB EM-26 part (64GB factory pre-configured as pSLC) and with a 32GB EM-20 part I manually reconfigured to 16GB pSLC (it was one my attempts with a bad image, but I confirmed the system booted and wrote correct syslog to that 16GB pSLC part).
- If you have the new chip connected to an MMC controller (vs. USB), pre-TRIM the entire device (blkdiscard Linux command) BEFORE you flash the image onto it to allow the emmc chip to use all unused space for wear leveling. Even if Tesla implementation issues TRIM commands, they are likely only for the filesystem and doesn’t trim unused areas outside of valid partitions. The chip might come pre-trimmed from the factory, but I saw nothing in the datasheets which guarantees it.
- Don’t forget to use ESD/grounding. ESD kills, just usually not instantly. In my career I’ve seem only a handful total/instant kills with accidental ESD, I have however seen many ESD damaged chips which kept on working, but damaged - e.g. they draw a lot more power and overheat due to damaged I/O buffers, or suffer from weird resets and data corruptions. While a lot of devices out there are ESD protected, chips are not always protected, so when you touch/work with bare boards and/or chips, use ESD precautions.
- Factory reset doesn’t clear out BT settings. After I finally rebuilt my image and successfully booted, even though I performed a factory reset twice, my phone re-connected to the MCU. Unfortunately, every time my phone connected, I lost all my audio from speakers (took me a few minutes to correlate the two, at first I just noticed audio when it first boots, then all audio gone). What solved it was manually unpairing the phone and re-pairing again.
- Take good high res pictures of your board before and after. After I finally rebuilt the image, I booted it successfully, everything worked except for backup camera. After some more investigation, I realized that on my 5th and final rework I managed to lose a tiny 10 Ohm resistor, which must be for impedance matching on one of the camera data lines. Replacing that resistor brought the camera back. Without good pictures, I would have never been able to track it down, as this board has a ton of unpopulated components. Here is the missing resistor (in case this happens to you):
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dark cloud
Active Member
Wow, sounds like a lot of work. Glad I paid someone else to do it
I am wondering though, could the browser now be working because of the odometer, browser and navigation history being lost (I think that is what you said) and therefore resetting?
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whitex
Well-Known Member
It would have been a lot less work if I didn't procrastinate (took one afternoon/evening to swap just once, never having done it before, though with some experience working on my Teslas and electronics rework tools at home), or had I known to check squashfs on top of fsck (in the latter case it would have been 1 rework instead of 5, and no re-balling which was a pain). On the bright side I got really efficient at it. I timed my last rework, unscrewing the MCU (dash already apart), taking off the BGA chip, careful cloning and reconstruction, putting a new BGA back on, and putting the MCU back in, I did it in 1h40m - if it was straight cloning I could probably get it down to just over an hour.Wow, sounds like a lot of work. Glad I paid someone else to do it
Even though it was a pain, I treat it as a learning experience, and up to three grand saved. No regrets.
Possibly the factory reset wiping out trip meters (not the odometer, that was part of car specific files which I recovered) and nav history helped the browser. There wouldn't have been much browser history to wipe, as I only ever used to use the tesla waze and one personal web page (most of the time it was just on Tesla Waze for weeks at a time, when it worked), other than when trying to connect to google when the browser stopped working. By no means am I sure that the browser will continue to work, just saying that it hasn't worked since at least v10 upgrade (I honestly don't remember the full screen loading Waze ever, the only times I have seen the full screen browser in the past was to be met with a blank screen, and I remember it not working on half screen already).
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dark cloud
Active Member
Yes, of course that is what I meant
I am sure Tesla mothership has a record of the odometer somewhere, and it would just reset the next time someone brought the car to life, or used a different MCU.Looks like they bumped the price of the MCU back up by $500. MIne was replacement recently and the MCU part was $1300. You might want to check on that. FWIW, I never got a written estimate in advance.
Recently I've been seeing many posts that start like this.... "I have not drove my car for weeks and my center screen is not coming on."
May 1st is when tesla retires old firmwares. Tesla is aggressively updating firmwares.
When eMMC's are old, update is one of the most frequent events that is the last thing a mcu does (dying.)
Please ask your friends and family to check on there pre-early-2018 S/X (mcu1) . If their car is having trouble installing updates, and their car is pretty old, there is a very good chance the eMMC is about to die. Even if their car is not old, we have seen eMMC's die in about 2 years, it is much more rare but it does happen.
Friends don't let friend's MCU die.
May 1st is when tesla retires old firmwares. Tesla is aggressively updating firmwares.
When eMMC's are old, update is one of the most frequent events that is the last thing a mcu does (dying.)
Please ask your friends and family to check on there pre-early-2018 S/X (mcu1) . If their car is having trouble installing updates, and their car is pretty old, there is a very good chance the eMMC is about to die. Even if their car is not old, we have seen eMMC's die in about 2 years, it is much more rare but it does happen.
Friends don't let friend's MCU die.
I just wanted to share with the community some advice after replacing my MCU1 emmc chip on a 2015 MS.
I knew my EMMC started to have issues, but was fooled by it not getting worse as long as I was not updating, and procrastinated for few months. Once I removed the emmc, it turned out the image was too corrupt to just do a simple transfer (luckily the car specific files survived intact). After 5 EMMC transplants later with some help from a kind samaritan with an image backup I could use to reconstruct the damaged parts of my emmc image, I now have an MCU1 faster than new and which will last 28 times as long as the original (7x P/E cycles * 4 times the size therefore available cells).
Some advice to share (things I did not see in some other howtos, or specific issues I happen to run into):
- Do not postpone your preventative EMMC replacement until it’s too late. I barely managed to recover car specific files due to my procrastination. I was slightly fooled by the fact that the MCU stopped getting worse when I started refusing updates and stopped streaming.
- With MCU out the DC-to-DC converter is not going to kick in to replenish the 12V battery, so a battery tender is a good idea if you are not disconnecting the 12V and HV batteries. HOWEVER, I found that if the car decides to run battery coolant pumps 24 hr a day, it will overwhelm even a 10 Amp battery tender and your 12V battery will be drained (happened to me twice in 7 days, as I was working on this only in the evening only, but with the COVID-19 it's not like I had anywhere to drive).
- Make sure you fsck check all your partitions, AND , and this is important (had I known this, it would have saved me A LOT of work) make sure you can unsquashfs partitions 1 and 2. If you cannot, no point soldering on a new EMMC chip, the MCU will not boot all the way.
- If you want best performance and longest life either reconfigure your new emmc to be 100% pSLC mode (cannot be done using the USB reader, only the SD one connected to an MMC controller - use "mmc enh_area set" command, WARNING, this is a one time operation, unreversible, so read up a little on how to use it), or buy it pre-configured from the factory as with the EM-26 series of Swissbit (which is just EM-20 series factory configured as pSLC). You get 7x the number or program-erase cycles, greater reliability, and faster I/O (read/write) performance over MLC mode – the only tradeoff is you pay twice the price for the chip since pSLC uses twice the cells for the same capacity (but given the effort to change it out, it was well worth the extra $35 to me). I got it to work with 32GB EM-26 part (64GB factory pre-configured as pSLC) and with a 32GB EM-20 part I manually reconfigured to 16GB pSLC (it was one my attempts with a bad image, but I confirmed the system booted and wrote correct syslog to that 16GB pSLC part).
- If you have the new chip connected to an MMC controller (vs. USB), pre-TRIM the entire device (blkdiscard Linux command) BEFORE you flash the image onto it to allow the emmc chip to use all unused space for wear leveling. Even if Tesla implementation issues TRIM commands, they are likely only for the filesystem and doesn’t trim unused areas outside of valid partitions. The chip might come pre-trimmed from the factory, but I saw nothing in the datasheets which guarantees it.
- Don’t forget to use ESD/grounding. ESD kills, just usually not instantly. In my career I’ve seem only a handful total/instant kills with accidental ESD, I have however seen many ESD damaged chips which kept on working, but damaged - e.g. they draw a lot more power and overheat due to damaged I/O buffers, or suffer from weird resets and data corruptions. While a lot of devices out there are ESD protected, chips are not always protected, so when you touch/work with bare boards and/or chips, use ESD precautions.
- Factory reset doesn’t clear out BT settings. After I finally rebuilt my image and successfully booted, even though I performed a factory reset twice, my phone re-connected to the MCU. Unfortunately, every time my phone connected, I lost all my audio from speakers (took me a few minutes to correlate the two, at first I just noticed audio when it first boots, then all audio gone). What solved it was manually unpairing the phone and re-pairing again.
- Take good high res pictures of your board before and after. After I finally rebuilt the image, I booted it successfully, everything worked except for backup camera. After some more investigation, I realized that on my 5th and final rework I managed to lose a tiny 10 Ohm resistor, which must be for impedance matching on one of the camera data lines. Replacing that resistor brought the camera back. Without good pictures, I would have never been able to track it down, as this board has a ton of unpopulated components. Here is the missing resistor (in case this happens to you):View attachment 536737
Interesting, I recently repaired a car where the reverse cam was not working, however it was due to an issue on MCU. Unfortunately they wanted their original MCU back so I don't get to look for a solution.
Nice job, for sure don't wait. The only reason I waited is I already had all my files and was ready to just build myself a new image. However things got so bad I could not reliable test new OpenPilot features so I had to switch before total death.
Actually looks like this is for a new MCU1 not a refurb. AFAIK they are still 8 gig chips.
I got a similar quote for the replacement of my MCU when I had my service on my drive unit. MCU NA PREMIUM MODEL S/X(1045006-00-J) Is the part number I was given and a $2K bill if i want it replaced with the unit. I would rather have the chip replaced with a more durable one. My MCU will need to be restarted every time the car goes to sleep. If the car is left alone for more then 15 minutes it will need to have the mcu restarted. luckily it comes back up but takes about a minute or 2 for the restart. I can still drive , but no climate control, blinkers. I can access the car settings with the remote app. The mcu doesn't seem to have an issue when it is on the home charger. Since i have to pull the whole mcu out i was looking at having the screen replaced with a good used or close to new one. mine has the light yellowing around the edges.
An unrelated note. I replaced the bubbling instrument cluster with a clean non-bubbling one from a 2015 model s. I still have the control board from the replacement since I just used the screen.
An unrelated note. I replaced the bubbling instrument cluster with a clean non-bubbling one from a 2015 model s. I still have the control board from the replacement since I just used the screen.
dark cloud
Active Member
You need to read this. Oh, and welcome to the forum
Thank you ! I'll give that a shot. I mean worse comes to worse and I will just replace the whole screen . I'm glad Tesla put enough thought into the dash assembly to at least make it fairly easy to take apart and put back together. My MS has needed some TLC for sure. I'm the second owner. The first had kids and wasn't the nicest with it.
The MCU on my 2015 Model S just died yesterday. No touchscreen, odometer blank, etc. The car was sitting in my garage for about 2 weeks unused (charging off and on). 105K+ total miles. Tesla Service quoted me $1492 for the "touchscreen to be replaced."
Looked over most of this long thread and reached out to a few of you all here. Not really sure what to do next. I don't want to lose any vehicle functionality first and foremost (base 85 with AM/FM/XM radio, LTE upgrade, etc). I also plan to keep this vehicle for as long as I can so don't want to have the same issue in a few years again (MCU1 vs MCU2).
I've replaced faulty door handles, broken HPWC, and other things myself but this disassembly definitely seems more involved.
Looked over most of this long thread and reached out to a few of you all here. Not really sure what to do next. I don't want to lose any vehicle functionality first and foremost (base 85 with AM/FM/XM radio, LTE upgrade, etc). I also plan to keep this vehicle for as long as I can so don't want to have the same issue in a few years again (MCU1 vs MCU2).
I've replaced faulty door handles, broken HPWC, and other things myself but this disassembly definitely seems more involved.
Add another one to the list. 2014 P85 with AP1. Touchscreen died a few weeks ago after attempting a software update. Reset/reboot didn’t help. Tesla app showed the update made it to 99%, but no luck getting it going again. Tesla support tried to diagnose it remotely, but the car is no longer connecting to WiFi, so they are no help. I really don’t want to spend $1800-$2000 on a refurb or new mcu v1 if the new infotainment upgrade will be $2500 for a new mcu v2, plus LTE (I have 3G now). I have a feeling I might be waiting for a while on that.
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gasmiser1
Member
Tesla Tech told me this today after replacement at their repair faculty. Also it’s LTE now.
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