MCU died, car now charging slow. Is this normal?

[MiamiDubai]

My MCU has the infamous black screen.
However I’m still able to connect to the car via the app.

I know it’s the Emmc issue.

My car is only charging at 8 amps versus the normal 32 amps, is this normal for a emmc failure?

Since the MCU is dead I can’t check to see if I can adjust the amps.

 

[gwxfer]

Yes, it normal for dead emmc.

 

[Zuikkis]

Also charge limit is gone, it will happily charge to 100% if you don't unplug it earlier..

 

[Rockster]

Also charge limit is gone, it will happily charge to 100% if you don't unplug it earlier..

Our car respected our charge setting after we uninstalled the MCU, removed the Terga board, and reinstalled the “dead” MCU while we waited for the upgraded Terga board. Perhaps there’s some difference between the behavior of an MCU in our case and one that has simply died.

 

[morrisdl]

...However I’m still able to connect to the car via the app....

Are you sure you can connect AND that the MCU is dead? Seems implausible.

Do you happen to know what version were you on? There is different default/limp mode behaviors depending on the version.
I sub to teslafi, so I could see mine was on 2020.40.0.4 when it died. Fulltime backup screen seems to be unique to my version.

My charge level is now locked to 80%.and the rate set to 240v/8A (2kw)
There is a thread here: Consolidated eMMC Thread (MCU repair) (Black Center Screen)

 

[MiamiDubai]

Are you sure you can connect AND that the MCU is dead? Seems implausible.

Do you happen to know what version were you on? There is different default/limp mode behaviors depending on the version.
I sub to teslafi, so I could see mine was on 2020.40.0.4 when it died. Fulltime backup screen seems to be unique to my version.

My charge level is now locked to 80%.and the rate set to 240v/8A (2kw)
There is a thread here: Consolidated eMMC Thread (MCU repair) (Black Center Screen)

Sorry meant to say my screen is dead.
I’m currently on 2020.36.11
Thanks for pointing me to that thread, looks like Tesla created a limp mode for when the emmc chip dies.

My A/C does turn off when I exit the car and my charging is limited to 8 amps. However my turn signals don’t function (weirdly my hazard lights work just fine) and my backup camera doesn’t show on the screen.

 

[MP3Mike]

I sub to teslafi, so I could see mine was on 2020.40.0.4 when it died. Fulltime backup screen seems to be unique to my version.

I knew I saw someone that said they had full time backup camera. So you got put in to "limited functionality" mode:

I saw a post that listed the other changes that this mode has, but I can't find it now. Things like:

• Displays only the rear view camera
• Sets HVAC to auto, so defrost works
• Sets headlights to auto
• Has changed how the turn signals work so that they should continue to operate
• Disables PIN to drive (I think)
• Disables scheduled charging (I think)

 

[Zuikkis]

Our car respected our charge setting after we uninstalled the MCU, removed the Terga board, and reinstalled the “dead” MCU while we waited for the upgraded Terga board. Perhaps there’s some difference between the behavior of an MCU in our case and one that has simply died.

Mine didn't have charge limit when Tegra board was removed. However, I had recently charged to 100% when the emmc failed. Maybe it remembers the setting it was set to?

 

[Zuikkis]

Sorry meant to say my screen is dead.
I’m currently on 2020.36.11
Thanks for pointing me to that thread, looks like Tesla created a limp mode for when the emmc chip dies.

My A/C does turn off when I exit the car and my charging is limited to 8 amps. However my turn signals don’t function (weirdly my hazard lights work just fine) and my backup camera doesn’t show on the screen.

My car had 3 minutes delay before turn signals started working. So they wouldn't work when you start driving, but then they were OK after a while.

But your car must have MCU working at least partially, if you can still access it with the app?

 

[Rockster]

Mine didn't have charge limit when Tegra board was removed. However, I had recently charged to 100% when the emmc failed. Maybe it remembers the setting it was set to?

Our removal and rebuild was done as a preventative when the very first signs of Emmc failure appeared. As such, we were able to set a bunch of things in anticipation of operating the car with the crippled MCU (i.e., no Terga board) reinstalled while the emmc was being cloned and replaced. For example, we made sure the lights were on automatic, the charge level was 80%, seats were set to the most common driver, etc.

I think the fact that yours failed with the car at 100% SOC is why it retained that setting, whereas ours hadn’t yet failed completely when we removed it.