Hacking Question Downgrading and efuses

[wolfidroid]

Is it possible to downgrade to a firmware after a newer version is installed and the fuses were burned?

 

[Witalka_Shelby]

No not possible.. :/

 

[Trekker]

The question is.. Why would you?

 

[OperationNT]

It's possible but the console won't boot anymore without payload injection. So it's useless.

 

[Bedel]

Well... As others said, it's possible. Te console won't turn on, but it is.
That said, it will turn on if you start the Switch FW from RCM since (afaik) that ignores the fuses. This could be usefull if it could be found an instalable exploit. This meaning somthing that you can install and still works when you update. But as for now, nothing like this exists, so it wouldn't give you much use.

 

[Itsuki235]

There is no way to boot vanilla OFW without RCM, without CFW after a switch has been downgraded.

So basically, yes downgrading is possible provided you use CFW and autoRCm after downgrading using ChoiDujourNX. Just make sure autoRCM is enabled and you have a way to inject a payload and run CFW. If already at 8.1.0, then you would need to restore from a NAND backup first since currently CFW does not work on 8.1.0.