# Update Battery Management System (BMS) Bootloader



## Ferd Ball (Aug 30, 2017)

Does anyone know what this does? The tech said that everyone needs it before they can get v9, and that you have to get it from the SC. I'm not sure I believe him.

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Concern: Update Battery Management System (BMS) Bootloader
Pay Type: Warranty
Corrections: Update Vehicle Firmware And Bootloader
Technicians performed update for vehicle firmware and battery management system
bootloader. Upon completion, verified proper function.


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## littlD (Apr 17, 2016)

Ferd Ball said:


> Does anyone know what this does? The tech said that everyone needs it before they can get v9, and that you have to get it from the SC. I'm not sure I believe him.
> 
> =-=-=-
> Concern: Update Battery Management System (BMS) Bootloader
> ...


What version did you have before this?


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## Ferd Ball (Aug 30, 2017)

34.1

I’m now on 36.2 and ready for v9.


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## 96s46p (Jul 5, 2018)

Surprising that you could even get to 34.1 without it as they were saying it was required long ago. I think mine was updated when I was on 21.x.


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## Ferd Ball (Aug 30, 2017)

What is it and what does it do and what is it?


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## 96s46p (Jul 5, 2018)

Battery Management System (BMS) - computer on the battery penthouse
Bootloader - lowest level software on the BMS that starts the system and loads the main software

Why does the bootloader have to be updated physically by a tech?
If something fails during the bootloader update then the whole BMS system is dead because the bootloader is the lowest level software. Too risky to self-update.

What was wrong with the old bootloader?
We don't know, just some bug that prevented it from working with newer BMS software.


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