I want to re-install A9LH on my 2DS, can I downgrade?

Discussion in '3DS - Flashcards & Custom Firmwares' started by Polarise, Nov 22, 2016.

  1. Polarise
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    Polarise GBAtemp Advanced Fan

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    Hello, I want to re-install A9LH on my 2DS because FBI is not working properly. Is it possible for me to downgrade my 2DS to 9.2 with A9LH when it is on v11.2.0-35?
     
  2. Quantumcat

    Quantumcat Dead and alive

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    In what way is it not working? How about we help you with that. It is dangerous to do the a9lh steps with a console that already has a9lh. Someone bricked from doing a DSiWare downgrade on an a9lh console.
     
  3. cravas

    cravas GBAtemp Advanced Fan

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    You can do a 9.2 CTR Transfer with the Decrypt9 payload.
     
  4. Polarise
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    Polarise GBAtemp Advanced Fan

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    At first when I would open FBI via the homebrew channel, it would say no kernel access acquired. (I can't inject FBI) so then I found an old nand backup of my 2ds and decided to restore it. After that, I went to the homebrew channel and FBI worked that time. So I decided to install the FBI CIA and that worked too. Everything is fixed.
     
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  5. Justin14p

    Justin14p GBAtemp Regular

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    Why downgrading a 3DS w/ A9LH causes bricks?
     
  6. Quantumcat

    Quantumcat Dead and alive

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    I think it corrupts the firm which is required for booting.
    Not all downgrades cause bricks on an a9lh console, I think just that one. But I think it's better to be safe than sorry (I think CTR transfer and restoring an older NAND backup could be said to be guaranteed safe. But I wouldn't try sysupdater or DSiWare downgrades)
     
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  7. Tenshi_Okami

    Tenshi_Okami GBAtemp Maniac

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    Normal downgrade doesn't cause bricks(since it uses CTR transfer)

    Maybe it bricked because A9LH needs a special NATIVE_FIRM? idk
     
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  8. Elaugaufein

    Elaugaufein GBAtemp Regular

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    The DSi downgrade writes to Firm0/Firm1. A9LH modifies those in order to work, at best you'd get a FrankenFirmware if a9lh correctly blocks the firm0/1 writes at worst you'd end up with junk in Firm0/Firm1 and thus a brick.

    If your a9lh console is functional enough to boot though, I'm pretty sure you can reinstall it, just by treating it like an a9lh payload update.
     
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