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Memory Chip Failures

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Older M S's are starting to have significant numbers of MCU failures out of warranty for $3 K expenses due to heavy logging activity in the chip. I have already had one dash cam USB failure in less than a year of use. Do all these chips have this vulnerability and does that include the M3? Would turning off data sharing reduce this risk? Tesla should address this since the logging is for their benefit.
 
Older M S's are starting to have significant numbers of MCU failures out of warranty for $3 K expenses due to heavy logging activity in the chip. I have already had one dash cam USB failure in less than a year of use. Do all these chips have this vulnerability and does that include the M3? Would turning off data sharing reduce this risk? Tesla should address this since the logging is for their benefit.
I'm not aware that there is a USB memory chip anywhere in the Model S (new or old). Could you enlighten us?
Dash cam USB? Are you referring to a USB memory stick that you added to record dash cam activity?
 
Don't know about the type of memory being used by the MCU but if your dash cam uses a Flash memory card (aka, SD/SDHC) then yes, it will have a limited lifetime. ANY Flash-based memory has this problem; some more than others. There is a limit as to how many times you can write and/or erase each memory bit. Today's memories are typically rated in the thousands of write/erase cycles. (multi-level bit designs like MLC, TLC or QLC). Which is why it's recommended to only use high endurance memory cards in dashcam/constantly over-recording video applications.
 
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I'm not aware that there is a USB memory chip anywhere in the Model S (new or old). Could you enlighten us?
It's not USB, but it's flash memory in another form factor (eMMC, basically like a soldered in SD card).

And yes, the Model 3 has the same kind of memory (but it's bigger, so it may take a bit longer to wear out). If Tesla doesn't reduce the system logging the Model 3 may have the same issues in a few years. This is not related to collecting Autopilot data etc.
 
It's not USB, but it's flash memory in another form factor (eMMC, basically like a soldered in SD card).

And yes, the Model 3 has the same kind of memory (but it's bigger, so it may take a bit longer to wear out). If Tesla doesn't reduce the system logging the Model 3 may have the same issues in a few years. This is not related to collecting Autopilot data etc.
eMMC and SSD flash storage is designed for many more write cycles than the cheap stuff they put in USB sticks. I've had eMMC and SSD memory running for years continuously in computers with no failures.
I still don't know what the OP is referring to with his "USB" dash cam memory. Is this a cheap USB stick he is using to record the dash cam? If so, this has no relation to the MCU memory.
 
eMMC and SSD flash storage is designed for many more write cycles than the cheap stuff they put in USB sticks.
Not necessarily. There are varying levels of endurance depending on the type and quality of the flash memory.
I still don't know what the OP is referring to with his "USB" dash cam memory. Is this a cheap USB stick he is using to record the dash cam? If so, this has no relation to the MCU memory.
The problem with the eMMC in MCU1 has been widely reported. You can find some threads about it over in the Model S section.
 
My cheap USB drive plugged into the port failed. With video being written to it continuously they apparently wear out. It's possible that video is written to the eMMC in th M3 also. My question was does turning off data sharing eliminate or reduce that. If so, I'll turn it off. If Tesla wants to keep accessing the data I want them to warranty that chip.
 
My cheap USB drive plugged into the port failed. With video being written to it continuously they apparently wear out. It's possible that video is written to the eMMC in th M3 also. My question was does turning off data sharing eliminate or reduce that. If so, I'll turn it off. If Tesla wants to keep accessing the data I want them to warranty that chip.
Looks like the eMMC chip is Linux data logging only and no way to turn that off. Tesla data logging goes to an internal SD card which is easy to replace. You should use a high quality USB for your webcam. Fortunately, that's easy to replace if it fails.
 
According to Phil Sadow who is in the Rich Rebuilds video, the problem is the MCU is doing Linux kernel logging continuously. Logging video too probably makes it worse.

I was just starting out as an Electronic Engineer when flash memory was first introduced and I did a design with the first generation flash memory. All flash memory has a max write limit per cell. It's always been there. The limit has improved, but it is still there. Constantly write to flash memory and it will eventually fail, no matter the quality.

There was someone who did a stress test of SSD drives writing massive loads to a number of different SSDs until they failed. All lasted past their design limits, but all failed eventually.

The problem that Tesla did was they left the Linux logging turned on, which provides no useful information for service. (The logs service check are written to a removable CD card on the MCU which can be replaced very easily.) This is written to a soldered in flash memory part that eventually fails when the write limit of the chip is reached and then the MCU quits working. Phil Sadow repairs these failures by replacing the chip and turning off the logging.

He said in the Rich Rebuilds video that Tesla has not changed this with new MCUs, it's just they are young enough they haven't failed yet.
 
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I was just starting out as an Electronic Engineer when flash memory was first introduced and I did a design with the first generation flash memory. All flash memory has a max write limit per cell. It's always been there. The limit has improved, but it is still there. Constantly write to flash memory and it will eventually fail, no matter the quality.
I'd have to say that, generally, the overall flash endurance limit has not been improving but instead it is getting worse. I've been a memory test engineer since 1979. I've had some small experience with NAND flash. Over the years of semiconductor process development the amount of storage available in each individual device has essentially expanded by three orders of magnitude (MB -> GB). Some of this is due to the memory cells physically getting smaller and some of it is due to multi-level cell (MLC) storage techniques. That results in the reduction of the number of times (cycles) you can erase and write each cell. There is a design which offers longer endurance than others and that's single level cell (SLC). Most of the flash memories today use one of the multi-level designs as people are usually more interested in being able to store more data in their device or having the lowest cost-per-bit, rather than being concerned about the number of times they can re-write it. SLC designs can typically reach 100,000 cycles while some of the newer MLC designs are rated in hundreds of cycles. Some flash memory manufacturers offer "high endurance" or "dashcam" memories which either use SLC or has a built in memory controller that uses a better wear leveling algorithm or has a more robust error correction system.
 
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