Naturally the MCU is the Media Control Unit. - Center screen. People are going to fuss that this is not entirely accurate. But I am trying to make it a bit more understandable. Think of it as the CPU of a Desktop computer system. The eMMC is like the main processor inside. The eMMC is mounted on a board called the Tegra board, named for a Video Graphics company. Now, think of the eMMC as a processor for storage data and the SD Media card you put in a camera. The eMMC wears out just like the camera SD Media. It takes a while. The operating system (OS) that the car uses is stored on the eMMC. Other files are also stored. Actions performed on the car like loading and saving/storing the OS. other critical files are stored there that the car needs. And, streaming data like music stores there temporarily, the car logs data to the eMMC too. Again, actions that the car takes use and wear out the eMMC. As it wears out it gets to a point it won't let the car boot/start up. That - I think - is what you are beginning to see more often on yours. Tesla can fix it. If its under warranty, cost will be nearly nothing. If you have to pay, it will be about $1600 including parts, labor and tax.The fix will likely last the next 5 years.
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