Tesla eMMC and MCU FAQ
Why do I need a new eMMC?
Your MCU has a "hard disk", this hard disk (ie eMMC) is limited to the number of read / write operations it supports. Unfortunately, Tesla made a "worse" decision when they chose the eMMC brand and size in their model S / X. Because they collect a lot (and by a lot, we mean a lot) of logs, this results in the eMMC starting to fail when they are about 3 -6 years. Of course, this varies a bit based on the mileage and the temperature around, several MCUs fail in the summer as well as during software updates.
When this eMMC starts to fail it will become apparent by little hiccups:
- Spotify crashes
- Browser crashes
- Navigation crashes/hangs
- No/intermittent BT/WIFI
- Complete hangs/reset of the system
- Black screens which can only be resolved by resetting via the steering wheel triggers.
As soon as you start to see any of these symptoms it's time to have your eMMC replaced.
In these cases, we have a 99.5% success rate.
If you wait too long however and the system will remain black, it becomes a bit trickier.
Sometimes - when you go to Tesla - they can "fix" it by reinstalling the software. However, this is not a real fix. They just reinstall the system on the already failed eMMC which will inevitably fail again. And so on. It is not a permanent solution. If you have a black screen, Tesla can fix it (by replacing the entire MCU with the same chip or only the tegra card). We are upgrading with better and bigger eMMC chips. If we fail to do so, you will only be charged for the installation time 1h.
If we can not fix a black screen, this means that eMMC has died completely and is not even recognized by the MCU anymore, which is something that is necessary for us to get the information needed to write the new chip. We can help you in these cases, but the process is a little longer.
Can you send the MCU or just the Tegra card to you and you repair it?
Yes of course, it's good to do, get in touch first. We only use proven methods (since 2017) and offer a 1-year warranty on the eMMC chip.
We recommend. everyone to review their insurance first. What does my insurance cover if I have a black scare or other error. What we do know is that most insurances cover a limited number of miles (type 12000 miles). After that, it is up to the customer to pay themselves.
When we take on the task of repairing / upgrading an MCU, we make sure that the customer benefits from settling through their insurance company. But if the car does not have insurance for the MCU and it is not black scarred yet, then it is the most optimal situation. Otherwise the risk increases that we can NOT help you. That it is not possible to save your eMMC (the data in it).
Upgrading your MCU (eMMC chip) for prevention is the best choice. Thus, check your mileage on the car. Check the terms and conditions with the insurance company. If these points are correct, do not wait too long. Get in touch as soon as possible for an appointment.
Do you still want to disassemble the MCU yourself? We are happy to help you with tips. Get in touch.
What happens when you cannot dump eMMC?
If we can not dump eMMC, it means that we can not get the certificates that are unique to your Tesla.
Because these are used to communicate with the Tesla server, it is not possible to do anything Internet related.
We can get the system up and running by using a generic image, but you can not get new updates or use your app. We can now help customers in these cases as well. It is a longer process but it is possible.
But I hear "experts" say that you can destroy the original eMMC when you dump data?
If you do not know what you are doing here, you should stop immediately. We do not remove the eMMC chip until the data / information is secured. We have our own method which involves a dumping of the data, without any risk to eMMC. Ie minimal risk, we do not put eMMC under any stress before we have data! The method has been proven for several years.
What does it cost when you can not dump eMMC?
Nothing if you decide you do not want the "generic image". But if you have chosen to use our mechanic to remove and replace the MCU from your Tesla, then these costs (1,000 SEK) must still be paid.
Are there any risks?
There are always risks, but no. If we can dump it, everything will be fine. We have the "know-how" needed for everything to work as usual again, if not better.
What can Tesla do / invalidate my warranty?
Tesla can do whatever they want with their software, which is great. The warranty on the MCU is already gone after the first four years, eMMC will behave in the same way and have exactly the same data as the original. It will only work (much) longer.
2021-01 News!: Congratulations to everyone who is within limits. Tesla now offers help to cars that are within these limits. 8 years or 160,000km. Check with Tesla.
After replacing the eMMC my 3G / supercharge sites / navigation / .... What can I do?
Usually when this happens it is due to a damaged P4. EMMC is divided into four partitions, of which P4 has your settings / preferences / supercharging sites and a few other things. We always try to reconstruct the whole original image to try to keep your personal settings, but sometimes P4 is too corrupt for this to succeed. Fortunately, your Tesla is smart enough (usually anyway) to fix the P4 yourself within a few days. But if you do not want to wait that long or it does not fix itself, you have to do a factory reset.
This can be done via your service settings in the menu and takes about 45 minutes.
What size of eMMC do you install?
The original eMMC Tesla uses is an 8 GB Hynix. Not the best quality and very small so it does not have much room for error correction. We now offer all customers a 64 GB Micron eMMC which will be approximately 20-40 times longer than the original.
How about 4G update, do you do that too?
We do, feel free to ask about prices for the 4G module. This is possible if you have an external SIM card (under the MCU). We will also need VIN and your name as we have to order these from Tesla. Since the SIM card itself usually only supports 3G, you / we must exchange this on Tesla for a 4G, should be about 300 SEK for the SIM card + work.
How long will it take?
You come with your Tesla, our mechanic does the removal / reassembly work.
We have to make an appointment for this, we need the car for 1-3 hours. If you are lucky, we can lend you a car, contact us first.
What are the prices and warrenty?
All of our work have 1 year warranty!
64 GB: SEK 6 000 SEK (inkl VAT)
excluding mechanics: - 2,000 SEK (and no guarantee from us when you assemble yourself, except the repair on eMMC on the Tegra card)
including 4G module: + 4,500 SEK
Can I have my dumped data?
Of course, just bring a 16 GB or larger USB stick and we are happy to copy data at no extra cost.
We can also upload it and send the link to you at no extra cost.
Do I notice a difference?
You will not notice a difference, but that's the point. Everything should work as usual, we have just extended the life of your MCU! Therefore, do not wait too long. Better to upgrade it now than for the MCU to shut down (get a black screen) and it usually happens when you need the car the most (inappropriate occasions).
Can I get Netflix, Youtube and other games on my MCU?
Yes !, with our retrofitted "Smartphone mirroring kit" you can look at what you want, whenever you want.
Tesla does not control it. See more info here
Contact us via email or whatsapp +46739492480
Note: EV Repair & Convert AB.