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MCU1 black after reboot, is it bricked?

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So I was driving today (100D, 110k km 2017), and noticed the outdoor temp display was blank. No issues, a reboot of the MCU would fix it. Boy was I wrong. The MCU screen went blank as expected, but it never came back on.

The car would still drive, the IC display is on, and I can even connect to it through the app (I can see the location but I can’t see charge % and most functions won’t work). Now, it is hard to drive it as is, no backup cam, can’t change climate, no signal turn noise etc...

I am out now so have no idea whether it would charge.

Called roadside assist and they said to try rebooting again in an hour. They don’t see anything wrong from their side.

Has anyone seen this before? Is my flash chip dead and needs an MCU1 replacement? It feels really bad to pay thousands to replace it with an outdated computer which will likely fail again in 2 years...
 
Ok this is not good. Can’t supercharge, and cannot use normal AC charge.
4788541F-EB76-45FC-8D6C-AB20B5155C22.jpeg
 
looks like emmc failure?
Maybe... I am ubering to the airport to get a rental car for the week. The next SC appointment is a week away, I hope they can look into and get it fixed sooner than that. I am out of warranty as I am over mileage... but the car is only 2.5 yr old.

It seems that the HVAC system is staying on, even when the car is parked at home. It is drawing 1-2kw from the AC line and I can hear it humming. Of course, without a working screen and remote access, there is no way I can turn that off.
 
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Should I drive the car to an SC before performing the 12V disconnect technique? It is still barely drivable now, and can still make it to the SC under its own power. Am concerned that if I disconnect and reconnect it, it will get to a state that it cannot be driven and needs to be towed.

Can I disconnect the fuse to the MCU for 5 min instead of disconnecting the 12V? Not sure where the 12V access is.
 
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Should I drive the car to an SC before performing the 12V disconnect technique? It is still barely drivable now, and can still make it to the SC under its own power. Am concerned that if I disconnect and reconnect it, it will get to a state that it cannot be driven and needs to be towed.

Can I disconnect the fuse to the MCU for 5 min instead of disconnecting the 12V? Not sure where the 12V access is.

if you know where the MCU fuse is - sure
 
I dunno if this had anything to do with it. I noticed that my maps were still circa 2018 last week and sent an service request to have them updated. It downloaded maybe 4GB and I got 2019 maps. 2 days later... my MCU 1 died, and the entire care is crippled as a result. Can’t charge, HVAC stays on and is effectively heating my garage.
 
Snowstorm, yes sounds like eMMC failure. Those folks above that told you this, I agree with them. Out of warranty cost is about $2300 parts and labor. You better get it to the SC while you have battery. Otherwise you just add to the headache and cost to move it there.
 
I booked an appointment but it is almost 2 weeks out, will try to call the SC tomorrow to see if they can get me in earlier. I hope they leave some walk-in room for these type of non drivable issues.

Do they replace the old MCU with an MCU2.0? I will hate to pay thousands only to get the same outdated unit which will probably break again in the same way in a couple of years.
 
You should try to move the car there - if they will accept it. Even if its going to be week+ before they can work on it. One never knows, they might have a cancellation and with it already there - work on it early.

Remember, its not going to charge. You don't want to be sitting in it with 20 miles or range at home on SC service day. If its at their SC parking lot, it becomes their responsibility to insure it does not brick.

No. You will get the same MCU that you have. Yes, we all hope like you, that we don't pay $2,000 and not get MCU2. We are hopeful that it will start soon. The rough estimate is there's 5,000+ across country that want to pay the estimated (at least) $2,000 to move up from MCU1 to MCU2. Someone posted story on Teslarati.com that he did it himself.
 
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Not likely emmc failure, since you can still access via app. You can try pulling the fuse or disconnect the 12V if your handy. You should try to drive in and see if they can service sooner.

Maps download to a separate card.

Maybe ask if service can re-push update to your car, and see if you can install it via app.

Likely to be different issue, since car cant charge, and heat is stuck on. However I have had a 2017 with failed emmc, so it's not totally ruled out.
 
He's connecting to the Mothership with the app (Tesla servers), but the car is not answering up.

The CID in the MCU has fallen and can't get up.
  • First thing I'd try is a hard reset. (Hold brake and two-finger salute)
  • If that doesn't do it then pull the MCU fuse for 30 seconds.
  • If that doesn't do it disconnect the positive from the battery and the emerg responders' cut-loop for 30 seconds.
If that doesn't do it, shoot yourself in the head, er, resolve to fix the eMMC using either my methods for a permanent solution, or hire ce2078 or TonyT (who uses my solution). Or pay Tesla to replace the MCU with a like unit and expect this problem to recur.

But whatever you do, do NOT allow that pack to drain, especially in freezing weather. While the MCU is getting fixed disconnect the positive from the 12v battery and the emerg responders' cut-loop. Do both.

Congrats, you might be the first 100D to fail like this.
 
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So I was driving today (100D, 110k km 2017), and noticed the outdoor temp display was blank. No issues, a reboot of the MCU would fix it. Boy was I wrong. The MCU screen went blank as expected, but it never came back on.

The car would still drive, the IC display is on, and I can even connect to it through the app (I can see the location but I can’t see charge % and most functions won’t work). Now, it is hard to drive it as is, no backup cam, can’t change climate, no signal turn noise etc...

I am out now so have no idea whether it would charge.

Called roadside assist and they said to try rebooting again in an hour. They don’t see anything wrong from their side.

Has anyone seen this before? Is my flash chip dead and needs an MCU1 replacement? It feels really bad to pay thousands to replace it with an outdated computer which will likely fail again in 2 years...
From what you've written I don't see that you've even tried a hard reboot of everything, never mind the power cut trick. Seems to me you are listening to doomsayers before even trying the basics. I don't see that you've even mentioned what version of the firmware you're running. How about you work through the common, obvious stuff before you assume one of the rare conditions is responsible?

Edit: Yeah, what rooter said (seriously helpful guy). I give it a 98% chance that one of his three bulleted items fixes your problem.