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Likely MCU Failure (MCU1 eMMC)

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Let's face it some of these cars cost upwards of 215k CDN brand new 4 years ago. Yes vehicles of this caliber price will require a large wallet to maintain after its 4-5 years old. Let's be honest. 1,200 US for a screen or 150 for a door handle assembly. Lots of used parts available online. Allot of DYI you tube videos on how to replace them with simple hand tools and a few hours... Jalopnik write ups are for trolls.

Let's look at a 5 yr old Mercedes diesel engine.... 35k CDN later...

I would expect for a 100k+ car that it shouldn't have such a glaring design defect.
 
Yes, but other 100k cars have issues too, like Stealerships that bend you over for routine maintenance. Said maintenance largely not required for EV's, so if you pay 2-4k for a major item like the screen after 4 years, consider the MB or BMW or Porche costs during that time.

Is this really true about maintenance though? It seems lots of DUs have failed, even amongst newer cars, and my thought is that maybe oil changes are wise and needed to help avoid some of these problems that develop over time. Ditto with coolant. Do we know if there’s a possibility of a gasket failing that would allow coolant and oil to mix, which would also require a maintenance to replace such a gasket? There is lots of tech talk here, which is good, but the absence of any mechanical discussion and the though that these machines should be maintenance free is troubling to me. I don’t think any company should get a pass on such a claim, even if the maintenance intervals might be longer due to gentler conditions when comparing ICE engines to EV drive units.

That stated, it seems thus eMMC issue is largely software/write volume driven and can be essentially mitigated by software changes that avoid the write volume. That’s more a bug/flaw/defect in my mind than routine maintenance that anyone should have to expect to cover. Just my opinion.
 
Yes, but other 100k cars have issues too, like Stealerships that bend you over for routine maintenance. Said maintenance largely not required for EV's, so if you pay 2-4k for a major item like the screen after 4 years, consider the MB or BMW or Porche costs during that time.

This doesn't matter. Tesla touts no maintenance, and this isn't even maintenance. It's a defect. It's one thing if it's an easily replaceable unit but to do the repair you either need to do BGA soldering or replace the whole unit.

This would be the equivalent of designing a car with brake pads that always rubbed against the wheels so they wore faster than they are supposed to. There is no reason for it, but you're stuck with it because of a poor design.

A properly designed system would minimize writes to flash memory and instead use a RAM disk for Linux logs.

Seriously, don't excuse them. They clearly dropped the ball, can fix it and they should.
 
Is this really true about maintenance though? It seems lots of DUs have failed, even amongst newer cars, and my thought is that maybe oil changes are wise and needed to help avoid some of these problems that develop over time. Ditto with coolant. Do we know if there’s a possibility of a gasket failing that would allow coolant and oil to mix, which would also require a maintenance to replace such a gasket? There is lots of tech talk here, which is good, but the absence of any mechanical discussion and the though that these machines should be maintenance free is troubling to me. I don’t think any company should get a pass on such a claim, even if the maintenance intervals might be longer due to gentler conditions when comparing ICE engines to EV drive units.

Oil changes in an ICE are necessary because the oil is subject to extreme heat and chemical changes from exposure to the byproducts of combustion. The drive unit fluid is similar to that of an automatic transmission and many manufacturers are simply sealing the whole thing off now and not recommending any transmission fluid changes. I know some people miss the whole wrench turning experience they had with an ICE but it's unnecessary for the most part.

That stated, it seems thus eMMC issue is largely software/write volume driven and can be essentially mitigated by software changes that avoid the write volume. That’s more a bug/flaw/defect in my mind than routine maintenance that anyone should have to expect to cover. Just my opinion.

That seems like it. I do Linux system engineering for a living and most of the logs you see have zero to do with the car's operation and would be just fine in a RAM disk. Any anomalies can be sent to Tesla remotely anyway if they really need to collect the data.
 
Look for anomalies - more lockups that require MCU restart should have been a clue for me. Car was disconnected AND had PIN to drive enabled - doh! It would not charge, would not drive and was completely disabled. Manually disengaged Supercharger and left for the Tesla approved towing company. Time to replace would have been half a day (granted they gave me priority as an out of town traveler), but it was Easter weekend and there were no engineers in Palo Alto on Saturday to generate proper firmware. They sent me home in a loaner and we exchanged the following Tuesday.

They keep MCU1s on the shelf for this, but they still have to schedule you in, get you in, replace the unit and generate and install fresh firmware.

The service center in Indianapolis was quite gracious and I ended up with an LTE upgrade in the process in my 83,000+ P85D.
 
Interestingly enough, I spoke with a Tesla mobile ranger who told me they are noW replacing MCU 1 with MCU 2. He said they have an adapter for the plugs and you get the full on new MCU 2 when it is replaced. Is that true- not sure, but I asked the question 5 different ways and he was pretty confident. As an aside, was told that this may not be public knowledge. Anyone out there have ANY confirmatory evidence that this is the case? I am skeptical, so I’d like to see something definitive...
 
I have had audio stutters, garbled fonts and "broken tiles" on the map (displays noise in a square instead of the actual map). I also had a weird bug last year where my MCU would crash (and reboot) everytime I drove at the same spot, but only during daylight (I figured it was also some corruption on cached data, the support was of no help and the problem eventually went away).

I have repeatedly contacted support and went to the SC to have them diagnose the issue, and their only response was "a firmware update will fix this" and "reset trip meters and recent locations in the nav".

Are those issues telltale signs that my MCU is starting to fail? What would the next failure be (blank screen.. random crashes and reboots..)?

As my warranty is coming to an end due to mileage, I'd like to get them to get me a new eMMC/MCU to spare myself the couple grand when my MCU will inevitably fail a few hundred miles past the warranty..
 
From those that have had this happen, are there any warning signs before the screen goes dead? I have a 2014 with 46k and it updated to new software ok last night, but I'm just curious to see if there is anything specific to keep an eye on.

Nothing I was smart enough to notice. The car seemed normal right up until the software install failed.
And, caveat -- at this moment, i do not know for sure that my car has had this exact failure. SC is looking into it.
 
Is there any way to have the system create extra write cycles? If so, you could intentionally cause the chip to fail while still in the warranty period.

I was just thinking about this for those who are close to out of warranty. Since it appears to log way more on screen button presses, it would probably be easy to make a little device with one of those touchscreen pens to just move up and down and continuously click many many times a button :cool:
 
Interestingly enough, I spoke with a Tesla mobile ranger who told me they are noW replacing MCU 1 with MCU 2. He said they have an adapter for the plugs and you get the full on new MCU 2 when it is replaced. Is that true- not sure, but I asked the question 5 different ways and he was pretty confident. As an aside, was told that this may not be public knowledge. Anyone out there have ANY confirmatory evidence that this is the case? I am skeptical, so I’d like to see something definitive...


Can you call or go back, and ask for part numbers for this and a cost.?
 
Update - strangely, my car was acting normal today and center screen had no glitches. Service center tech called me this afternoon and said that they would push me the newer, just-released software version to see if it fixes the problem. He didn't think it was the eMMC.

Downloading the update as I'm typing, so keeping fingers crossed.