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MCU1: Black center screen / mcu failure caused by a faulty navigation MicroSD card

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I would recommend you get the "Extreme" or "Endurance" class cards instead of the Ultra or whatever. The Ultra will likely last as long as the original SD card, but the Extreme cards, which several manufacturers offer, are designed for extreme hot, cold and harsh environments like cars, and are able to be rewritten over and over for 10 years.
 
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I considered the SanDisk extreme but don't think it makes a difference as the ultra is also rated for high/low temperatures. The only real difference I saw was the extreme is "gopro approved". I reckon gopro charged plenty for that endorsement explaining the higher price.

As for high endurance it doesn't apply for this application. It just means it is made for many write cycles such as dash cams. Maps are rarely updated and a specific sector on the card is only written every other map update.

But we'll see. If my new card dies I'll be sure to update this thread. Considering the original 2013 card lasted 9 years in Texas heat I'm pretty confident the new one will be ok for a while.
 
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Reactions: Droschke
I considered the SanDisk extreme but don't think it makes a difference as the ultra is also rated for high/low temperatures. The only real difference I saw was the extreme is "gopro approved". I reckon gopro charged plenty for that endorsement explaining the higher price.

As for high endurance it doesn't apply for this application. It just means it is made for many write cycles such as dash cams. Maps are rarely updated and a specific sector on the card is only written every other map update.

But we'll see. If my new card dies I'll be sure to update this thread. Considering the original 2013 card lasted 9 years in Texas heat I'm pretty confident the new one will be ok for a while.
Your old SD card failed because it got too many writes. Your replacement card will last as long, which is likely plenty of time. The MCU1 memory replacement was also for this same reason, it got too many writes and started losing its useable space, just like the SD card.
 
Out of curiosity I looked up environmental specs for SanDisk. From SanDisk cards environmental tolerance (waterproof, temperature, magnetic and x-ray proof).

SanDisk has tested its SD, SDHC, microSD and microSDHC memory cards under a variety of tough conditions. Our standard, SanDisk Ultra, SanDisk Extreme, and SanDisk Mobile Ultra lines (up to 32 GB) are capable of withstanding the following conditions:

Temperature proof:
SanDisk SD, SDHC, microSD and microSDHC memory cards are capable of withstanding operating temperatures from -13ºF to 185ºF (-25ºC to 85 ºC).


Interestingly enough they don't publish write cycles but even cheap MLC memory is rated 10,000 writes. In our cars I think the limit will just be breakdown due to age.
 
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Navigation card is only written when there is a map update, so only a few times a year. So write endurance is not an issue, they simply die because of the heat.
Navigation maps are cached for the areas you are driving in. So the display refreshes quickly as you are driving. Also past NAV destinations and likely some route info are dynamically cached. The card is constantly written to and changing.
 
Navigation maps are cached for the areas you are driving in. So the display refreshes quickly as you are driving. Also past NAV destinations and likely some route info are dynamically cached. The card is constantly written to and changing.

No. You can try remove the card, it will contain exactly the same data that you have initially written.

Nav card uses squashfs filesystem. From Wikipedia: "Squashfs is a compressed read-only filesystem for Linux."

All caching takes place on the main emmc.
 
No. You can try remove the card, it will contain exactly the same data that you have initially written.

Nav card uses squashfs filesystem. From Wikipedia: "Squashfs is a compressed read-only filesystem for Linux."

All caching takes place on the main emmc.
Interesting. I am surprised the failure rate is so high based on age and environmental conditions alone.
 
No. You can try remove the card, it will contain exactly the same data that you have initially written.

Nav card uses squashfs filesystem. From Wikipedia: "Squashfs is a compressed read-only filesystem for Linux."

All caching takes place on the main emmc.
Yep, and the whole point of the large, once a year, map download is that you have the entire area stored/cached on the SD card.

Navigation maps are cached for the areas you are driving in. So the display refreshes quickly as you are driving.
I assume you were actually talking about caching the satellite view maps that are downloaded over the cellular network in the area you are driving in. And yes, those are cached but on the main eMMC. But those have nothing to do with navigation.
 
I assume you were actually talking about caching the satellite view maps that are downloaded over the cellular network in the area you are driving in. And yes, those are cached but on the main eMMC. But those have nothing to do with navigation.
Yes, and all cars earlier than 2018(?) would have free unlimited cellular data connections to support google earth maps. I am very surprised this is not stored with the other map data. Must have been too slow to read from the SD card on those earlier SD cards, so they used the MCU memory.
 
Yes, and all cars earlier than 2018(?) would have free unlimited cellular data connections to support google earth maps. I am very surprised this is not stored with the other map data. Must have been too slow to read from the SD card on those earlier SD cards, so they used the MCU memory.
I suspect that Google has conditions on how many satellite tiles can be cached and for how long, and since they use a compressed read-only file system to store the files on the SD card it makes no sense to try to store data that is changing on almost every drive there.
 
Is there an update on buying a pre-formatted card at this point?

OR

can i just install a new SD card out of the box and have Tesla remotely initialize and push out the updates to it?
I just finished replacing my Nav SD card today. I tried using a SanDisk 32GB card first and asked Tesla to have a remote tech partition and format it, but nothing happened since Friday and today they responded that I was in the que, but it could take 2-3 days. They had ordered a pre-loaded card for me last week and it arrived late today, so I got it and pulled the MCU again. Nav routing worked again immediately and a 2022 update is downloading now. Unless you can partition and format a standard uSD card for Linux, using the Tesla SD card for $20 is worth it.
 

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I just finished replacing my Nav SD card today. I tried using a SanDisk 32GB card first and asked Tesla to have a remote tech partition and format it, but nothing happened since Friday and today they responded that I was in the que, but it could take 2-3 days. They had ordered a pre-loaded card for me last week and it arrived late today, so I got it and pulled the MCU again. Nav routing worked again immediately and a 2022 update is downloading now. Unless you can partition and format a standard uSD card for Linux, using the Tesla SD card for $20 is worth it.
That's great! Curious, did you pull the entire MCU out of the dash or do the HVAC duct hack? Is it bad to remove the MCU? I tried watching a few YT videos but most of them require removing both of the dash trim etc. I'm pretty handy but a bit intimidated with all those clips etc. and something breaking.
 
I just finished replacing my Nav SD card today. I tried using a SanDisk 32GB card first and asked Tesla to have a remote tech partition and format it, but nothing happened since Friday and today they responded that I was in the que, but it could take 2-3 days. They had ordered a pre-loaded card for me last week and it arrived late today, so I got it and pulled the MCU again. Nav routing worked again immediately and a 2022 update is downloading now. Unless you can partition and format a standard uSD card for Linux, using the Tesla SD card for $20 is worth it.

I was not aware Tesla sells Micro-SD cars pre-loaded with maps. How much do they charge?

What's the version of that map?

Thanks.
 
That's great! Curious, did you pull the entire MCU out of the dash or do the HVAC duct hack? Is it bad to remove the MCU? I tried watching a few YT videos but most of them require removing both of the dash trim etc. I'm pretty handy but a bit intimidated with all those clips etc. and something breaking.
If you ever played with LEGO you can take the Model S dash apart. Seriously, it's simple. All the screws are identical except two which are a different color so easy to tell apart. No need to disconnect any cables from the MCU, just remove dash on both sides and tilt the MCU forward enough to get to the slot.