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Model S/X eMMC MCU Replacement - Warrenty Adjustment Program

Hello there,

I have been battling an extremely laggy and frequent self-restarting MCU1 in my 2017 Model X. The MCU would reboot itself constantly while driving and sometimes would last extended periods of time. Outages would last from 3 minutes to at it's longest 15 minutes. On average this happens about 2 times per week.

I have been to my service center addressing this issue 5 times now. Every time I go in I get the usual drill of "we flashed the memory", "cleared the cache", etc. I scheduled another visit for this coming Monday to look at it again. As it so happens I just received this email from Tesla (below) stating that my MCU1 eMMC module can cause failure in the MCU and can be replaced. Fantastic news! Slightly frustrating though that I had to find this out from an automatically generated email and not from the service center reps I have been on the phone with.

As it appears this service advisory was issued November 9th. I am wondering if anyone has had this maintenance performed yet? I have read on these forums that a number of individuals are having the same MCU issues that I am. I also wonder if any performance increase has been realized. I absolutely hate the laggy touch screen and find it unnecessary to spend $2,500 on the MCU2 upgrade to fix this. In my opinion though a $100,000 car should not have such a unresponsive infotainment system. Fingers crossed for this fix!


Warranty Adjustment Program
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Active Member
Supporting Member
Nov 13, 2017
Edwardsburg, MI
Hi @studioloft,

Per the letter you mentioned they will/should replace the daughterboard in your car MCU1.

You may ask about the replacement - Do they have the part???
They are replacing it in a total fail situation...

Some have paid to have the daughterboard replaced.
I think it was from $200 to $500 if done proactively.

From those that had the daughterboard replaced, they have not reported
faster speeds or better performance. Browser still bad...
BUT at least the car functions without the constant reboots...

Good luck,

I've seen it discussed more in the Model S forums, but there is a notification/warning that pops up in vehicles that is an unofficial gating tool for doing the warranty replacement. Your service history may help, but don't be surprised if they decline the warranty until you have said notification.

This post (#112) and the subsequent )#113) have the images of what you would see.

Tesla Covering MCU1 Issues!!

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