That's not to entirely excuse Tesla. If you have a modern operating system running from flash that needs to work for 20+ years as people expect from a car, it needs to be very carefully designed - all logging and runtime data written only to a RAM disk, system and user data on entirely separate partitions, etc.
Note that this doesn't excuse Tesla here, since the situation I discussed is very rare, normally if that module fails the vehicle will still start and run. Tesla engineers should absolutely have been aware of this issue, as pointed out up thread there are multiple tutorials for ras-pi SD memory preservation, and I have trouble believing a competent EE shouldn't be aware of life issues due to eMMC. It also shouldn't brick the car, normally automotive electronics are designed very carefully to avoid single points if failure, with fallback routines and safety "limp-home" modes in case of problems.
Wasn't preventing this one of the design goals/selling points of CAN?
Near as I could tell from my scope, the APIM was spamming the bus with exactly the right frequency to interrupt the ECM during it's scan of critical sensors. It was an extremely rare failure, and to Ford's credit they covered both the repair as well as my shop's diagnostic time.
edit: To make it clear, I have seen 2 vehicles that still operated with a direct CANBUS short to ground, as well as a vehicle that had CANBUS shorted to 12V+. In these cases, aside from expected failures (such as the BCM systems not responding, or transmission limp-home), modules were able to fall back into either safe states (limp-home, in the case of the TCM) or just a dashboard warning light (in the case of BCM no-comms).
Thanks for the anecdote!
The car won’t run when the eMMC chip fails, and Tesla solution is a new MCU board which costs $2,700 out of warranty. Not surprisingly Tesla is not desoldering and reworking just the eMMC chip.
There are any number of components that can disable a car, from the battery to the starter to something with the ignition, electronics, anti-theft, etc.
Sometimes the repair is as simple as a new battery, sometimes the repair is an expensive piece of hardware.
Now if the article was that Tesla Model S has a chip which wears out and the board holding the chip is expensive to replace, and maybe even getting into why don’t they push a software update to lower the writes to that chip — I would not disagree.
The article falsely claimed the cars are “bricked”. As it’s the main thrust of the article, it should be retracted.
> However, until the company starts stocking parts like the eMMC chip, as well as release detailed service manuals to the public, Tesla is going to be looking at a number of newish cars dead in a junkyard real soon.
They should stock a chip which is soldered to the board, and what, do reworks? That’s asinine.
Newish cars dead in a junkyard? Totally false. It’s an expensive repair for a problem that could have been avoided, and hopefully Tesla will remedy with a firmware update.
This is the board the chip is on, which Tesla does not offer to replace: https://share.icloud.com/photos/0u78AylGb9fv8QHQnyr9IC3nA
This is what Tesla will offer to replace: https://share.icloud.com/photos/0MVG8edJheaHYiEp7yWKkVePg
Is that what you were imagining?
Why a full memory chip logging data which is never used should brick a car is simply price gouging.
There is no need for it whatsoever.
Thousands of dollars to replace a board because of a full memory chip? That is even worse than Apples repair racket, at least in Apple's case some other circuitry besides memory is faulty - https://www.youtube.com/watch?v=2yJKix17yYE
1. Log something they never read back
2. Use a soldered down chip (they use a SD card in other locations)
3. Crash the media controls when the unused logs cannot be written
4. Disable certain car features, potentially immobilizing the vehicle because the media center is off.
There are several ways that Tesla could have prevented this issue, and the fact that they've never bothered to resolve the issue in later iterations is just baffling.
I suspect "we can fix it in a software update" lowers the priority of actually shipping this design.
and then add in "autopilot this year" and "model y coming soon", you get indefinite postponement.