Hacking Unable to boot after restoring nand

[raphzthename]

For context:

• 4.0 Switch nand backed up with Hekate
• Updated OFW to 5.1
• Nand restore to 4.0 backup with Hekate

Both `boot0/boot1` and `rawnand` were restored and verified successfully.

I am now unable to boot up normally, which I assume is because the OFW update to 5.1 burned one fuse and my original 4.0 nand backup had zero burned fuses. I think I understand that part and I've read that it's still possible to boot into hekate to bypass the fuse check and boot into stock firmware. I'm unable to do so.

Steps:

• Put switch into RCM mode
• Boot into hekate
• Select Reboot (Normal)
• Screen remains black

How can I boot back into OFW?

 

[jakkal]

if you have more burnt fuses than what 4.0 requires then youre out of luck (if you dont have a 5.1 backup)

 

[Uumas]

When you boot into Hekate you don't select reboot, but Launch -> Stock.

 

[raphzthename]

When you boot into Hekate you don't select reboot, but Launch -> Stock.

Thanks. What's required to be on the sd card if I just want to launch this way?

 

[Uumas]

Thanks. What's required to be on the sd card if I just want to launch this way?

Nothing else than hekate_ipl.ini in the bootloader folder. Add "[Stock]" before the brackets so that it looks something like this:
[config]
autoboot=0
autoboot_list=0
bootwait=5
backlight=100

[Stock]
{ }
The yellow lines aren't required and there might be some other options, but just let them be.

 

[raphzthename]

Nothing else than hekate_ipl.ini in the bootloader folder.

Awesome! Working great now.

A couple of final questions:
1. I flashed back to 4.1.0. Is it possible to upgrade to 5.1 or will the official update force 6.0?
2. Since I have already upgraded from 4.1.0 to 5.1 before, will I burn another fuse upgrading again (assuming I can flash to 5.1)?

 

[Uumas]

Awesome! Working great now.

A couple of final questions:
1. I flashed back to 4.1.0. Is it possible to upgrade to 5.1 or will the official update force 6.0?
2. Since I have already upgraded from 4.1.0 to 5.1 before, will I burn another fuse upgrading again (assuming I can flash to 5.1)?

1. Online update will update to 6.1, if you want 5.1 use ChoiDujorNX or a game cart with 5.1 on it.
2. No. Every time you boot the console (without rcm) it checks how many fuses are burnt. If there's too many fuses burnt, it'll not boot and if too few, it'll just burn more until it matches the amount required by the firmware. Let's use 3.0.1 as an example: It requires four fuses to be burnt. If you for example just updated from 3.0.0, which requires 3, it'll burn one fuse. On the other hand, if you tried to downgrade from 4.x which burns four fuses, you can't boot 3.0.1 or lower anymore.
TL;DR: Fuses don't get burned while updating, but when first booting a new firmware