3DS:Error screens/Luma3DS exception screen

This page lists possible causes and fixes of Luma3DS exception screens. They are not applicable to every situation, but cover most common known issues.

Reading a Luma3DS exception screen

A Luma3DS exception has four (or five, in a few cases) different parts to it that help in finding its cause, as follows:

• Processor: What part of the system is causing the exception. The two processors are:
  • Arm9: The 'security processor' of the system. These exceptions are usually raised because of errors in NAND data or hardware faults in either the 3DS or its SD card.
  • Arm11: The 'userland' of the system. These exceptions have numerous causes but are more often related to broken software or user data.
• Exception type: The type of fault that caused the exception. These categories correspond to the ARM exceptions for the ARM9 and ARM11 CPUs, as follows:
  • data abort: Caused by a read or write to an invalid part of memory. Usually related to game mods/cheats/plugins, broken HOME Menu data, and/or broken CFW applications.
  • prefetch abort: Caused by an attempt to execute an invalid CPU instruction. Often related to conflicts between CFW and other software.
  • prefetch abort (svcBreak): Caused by either Process9 or homebrew software manually terminating code because it matched a pre-defined condition. Often related to errors in NAND data, even when raised by Arm11. Can also happen when launching an out-of-region game that isn't locale emulated.
  • prefetch abort (kernel panic): Caused by Kernel9 detecting an unrecoverable fatal error and forcibly shutting down to avoid damage. Can be related to any of several things, but hardware issues are the most likely.
  • undefined instruction: Caused by an attempt to execute a CPU instruction that was unimplemented, disallowed, or unusable. Often related to software not having the required files (if not on boot) or an outdated boot.firm (if on boot).
• Fault status: The specific type of ARM exception that was raised. Helpful for developers, but not so much for the end user.
• Current process: Where the error is coming from in the system. Often the most helpful part of the exception. Some examples of processes are as follows:
  • fs: The filesystem, i.e. either the SD card or the NAND.
  • menu: Data that is opened either as a part of the HOME Menu or at the same time as it.
  • loader: The service that opens apps, meaning the app most recently opened has an issue.
  • nwm: Networking services, almost always WiFi.
  • ns: The Nintendo User Interface Shell, which handles all apps/processes/services in 3DS mode.
• R0: Usually just internal data that's not worth reading. There are two notable exceptions, however:
  • Arm11 loader exception: If R0's contents start with a C or D, R0 is an error code. This code usually gives the exact cause of the issue.
  • Arm11 pm exception: If R0's contents are E0E01BF5, boot.firm is guaranteed to be too outdated to work.

Known Errors

In the following list, the file prefixes on file paths refer to the starting location. sd:/ refers to the SD card, and numbers in the format of [X:] refer to GodMode9's drive numbers.

If the below fixes do not solve your issue or you are unsure of what to do, join the Nintendo Homebrew Discord for further assistance.

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Arm9

Arm9 errors are sorted by their exception type.

Error On Boot

Any Type

• Files on the SD are corrupted.
  • To fix, verify that the SD card is not faulty. If it is verified working, make a backup of all intact files, format the SD card, and try booting again.
• A system save located on the NAND in [1:]/data has a problem.
• System-unique files are missing from the NAND in [1:]/rw/sys.

data abort

• The shared2 folder in [2:] SYSNAND TWLN is missing.
  • To fix, create this folder.
• System titles have been deleted.
  • To fix, perform a Safe Mode update.
    If this does not work, perform a CTRTransfer.

prefetch abort (svcBreak)

• The system movable, [1:]/private/movable.sed, is 288 bytes but a flag is enabled that expects a size of 320 bytes.
  • To fix, boot into GodMode9 and select SYSNAND CTRNAND, then go into the private folder.
    Inside this folder, you will see a file named movable.sed. Select it, and under the options menu, select Show in Hexeditor.
    Green-colored numbers will appear in the middle of the screen - press A and then unlock writing to sysNAND (lvl2).
    At the beginning of the file, look for the set of numbers 53 45 45 44 00 01. Once you find these numbers, hold A and press D-PAD DOWN while the 01 value is highlighted to change it to 00. Press B, then A, then B to save changes and exit from the hexeditor, then press START to reboot your console.
• SYSNAND CTRNAND has bad CMACs.
  • To fix, press R+A on the SYSNAND CTRNAND drive and Fix CMACs for drive. The console will act like it has been formatted after this, and this is intended.
• If none of the above have worked, perform a Manual CTRTransfer.

prefetch abort (kernel panic)

• The console likely has a hardware issue.

undefined instruction

• The console likely has a hardware issue.

Error During Use

data abort

• Files on the SD are corrupted.
  • To fix, verify that your card is not faulty. If it is verified working, make a backup of all intact files, format the SD card, and try again.

Arm11

All Arm11 errors are sorted by their current process.

Error On Boot

act

• Your NNID(s)' stored data is misconfigured or being interfered with.
  • To fix, if Pretendo is installed, turn it off by disabling Enable loading external FIRMs and modules on the Luma configuration menu.
    • If this does not help or Pretendo is not installed, then restore a NAND backup - especially if you recently tried to log out an NNID.

boss

• The current firmware version is too old for SpotPass to work. Perform a Safe Mode update.
  • If this does not work, you may require a CTRTransfer.

cfg

• Either the NAND config savegame or part of your console-unique file(s) is damaged.
  • To fix, first boot into GodMode9, press R+A while the cursor is on the folder [1:]/data/<ID0>/sysdata/00010017, choose to Copy to 0:/gm9/out, then delete the folder. After rebooting, the console will enter initial setup again; this is intended and not an issue.
    • If this does not help, delete the newly created 00010017 and copy the backup into its place, run 3DS:ctrcheck, and replace any console-unique files marked as invalid or missing with the copies from the essentials.exefs backup inside [S:] SYSNAND VIRTUAL in GodMode9.

fs

• Could be an SD card problem, minor NAND problem, hardware issue, or anything in between.
  • fault isolation will likely be required to find the true cause of this error. Start by doing ctrcheck and trying to trigger the error with the SD card removed from the console.
    If the error stops when the SD card is removed, reformat the SD card, and if that doesn't help, test it for hardware damage.

hid

• Potential hardware problems, or an outdated version of Rehid.
  • First look for and delete /luma/titles/0004013000001D02 and /luma/titles/0004013000003302. If these don't exist, or Rehid has never been installed on this console, it's likely hardware issues.
    • 3ds_hw_test or ctrcheck may help with fault isolation.

ic2/gsp/mcu/pxi/spi/

• The console has a serious hardware issue that is likely not easily fixable.
  • Run 3ds_hw_test. If the test returns zero errors detected, join the Nintendo Homebrew Discord and ask, in English, for help.

mset

• System Settings is broken in some way - this may indicate that the console has a hardware issue.
  • To fix, perform a CTRTransfer, or a Manual CTRTransfer if that does not work.
    • If neither of these work, the console has a serious issue. Join the Nintendo Homebrew Discord and ask, in English, for help.

menu

• data abort

  • The installed theme is corrupted or otherwise broken.
    • To fix, go into the folder sd:/Nintendo 3DS/<ID0>/<ID1>/extdata/00000000/ and delete the folder matching your region, one of the following:

    USA: 000002cd
    EUR: 000002ce
    JPN: 000002cc

  • The HOME Menu's extra data is corrupted.
    • To fix, go into the folder sd:/Nintendo 3DS/<ID0>/<ID1>/extdata/00000000/ and delete the folder matching your region, one of the following:

    USA: 0000008f
    EUR: 00000098
    JPN: 00000082
    KOR: 000000A9

  • An installed application is corrupted or otherwise broken.
    • To fix, either perform a Safe Mode update, attempt to enter System Settings before the crash occurs and delete the application in Data Management, or reformat the SD card.

• prefetch abort

  • An installation of Menuhax is conflicting with the custom firmware.
    • To fix, follow the directions on this page.
  • If this occurs on boot, set Hbmenu autoboot in the Luma configuration menu to 3DS, then follow the above instructions and turn Hbmenu autoboot back off once it has been removed.
    • Ensure in sd:/luma/config.ini that hbldr_3dsx_titleid is set to 000400000d921e00 and boot.3dsx is in the root.

• prefetch abort (svcBreak)

  • The f000000b folder in SYSNAND CTRNAND is broken, its exact location being at [1:]/data/<ID0>/extdata/00048000/f000000b.
    • To fix, backup f000000b by pressing R+A while highlighting it, then selecting Copy to 0:/gm9/out. Once it is backed up, delete the folder. If this does not fix the issue, copy the folder back where it was.
  • If you have a recent NAND backup, try restoring it with this guide

ns

• The Luma configuration setting Hbmenu autoboot is set to boot to a title that does not exist.
  • To fix, disable the option, install an application with the title ID in sd:/luma/config.ini, or change the set title ID to match an application that does exist.

nwm

• The WiFi chipset's hardware is damaged or dead.
  • To fix, replace the WiFi chipset with a new one. To avoid the error until then, disable WiFi on the 3DS and do not turn it back on.
    • If the 3DS is an old model, you can disable WiFi using an external switch. New models do not have this switch disable it through the HOME Menu Settings or Rosalina. Repeatedly pressing the keycombo for Rosalina while powering on might let you access Rosalina before it can crash.

pm

• The installed version of Luma3DS likely does not support the current firmware version. This is guaranteed to be true if the contents of R0 are E0E01BF5.
  • To fix, update CFW.

Error During Use

3dsx_app

• The .3dsx file that was most recently opened is corrupted.
  • To fix, download a new copy of the .3dsx file. If this error happens when opening the Homebrew Launcher, download a new copy of boot.3dsx.

    If the error still happens, test the SD card for errors.

app/CtrApp

• If not prefetch abort (svcBreak): The app most recently opened is trying to use broken software.
  • To fix, disable all game mods, cheat codes, and plugins to ensure they are not the cause.

    If the error still happens, then the game itself is likely faulty. If it is a system app, perform a CTRTransfer. Otherwise, if it is a cartridge dump, redump it, if it is an eShop game, click the Repair button at the bottom of its eShop page or delete and reinstall it, or if it is a cartridge, clean the cartridge and the 3DS cartridge reader with isopropyl alcohol.

• If prefetch abort (svcBreak): The app most recently opened is out-of-region and relies on locale-specific data. Activate locale emulation for it.

GARDEN

• Animal Crossing's game data or savedata is having issues.
  • To fix, disable all game mods, cheat codes, and plugins to ensure they are not the cause. If the error still happens, then the game itself may be faulty. If it is a cartridge dump, redump it, if it is an eShop game, click the Repair button at the bottom of its eShop page or delete and reinstall it, or if it is a cartridge, clean the cartridge and the 3DS cartridge reader with isopropyl alcohol.
    • If the error yet still happens, ensure that you have not used a save editor before the error started happening. If you have used a save editor, the edits are broken and you will need to restore a backed-up save, or wipe the save and start over if you have no backup.

fs

• Could be an SD card problem, minor NAND problem, hardware issue, or anything in between.
  • fault isolation will likely be required to find the true cause of this error. Start by doing ctrcheck and trying to trigger the error with the SD card removed from the console.
    If the error stops when the SD card is removed, reformat the SD card, and if that doesn't help, test it for hardware damage.

Kujira/Joker/niji_loc

• The app most recently opened has an issue of some kind.
  • To fix, disable all game mods, cheat codes, and plugins to ensure they are not the cause. If the error still happens, ensure the game is the same region as the console - if it is not, activate locale emulation for the game.
    • If the error yet still happens, then the game itself is likely faulty. If it is a cartridge dump, redump it. If it is an eShop game, click the Repair button at the bottom of its eShop page or delete and reinstall it. If it is a cartridge, clean the cartridge and the 3DS cartridge reader with isopropyl alcohol.

loader

• The app most recently opened has an issue. If the contents of R0 start with C or D, R0 is an error code.
  
  • Most of the possible error codes for this are listed on this page.

mset

• System Settings is broken in some way - this may indicate that the console has a hardware issue.
  • To fix, perform a CTRTransfer, or a Manual CTRTransfer if that does not work.
    • If neither of these work, the console has a serious issue. Join the Nintendo Homebrew Discord and ask, in English, for help.

nwm

• The WiFi chipset's hardware is damaged or dead.
  • To fix, replace the WiFi chipset with a new one. To avoid the error until then, disable WiFi on the 3DS and do not turn it back on.
    • If the 3DS is an old model, you can disable WiFi with an external switch. New models must instead disable it through the HOME Menu Settings or Rosalina. Repeatedly pressing the keycombo for Rosalina while powering on might let you access Rosalina before it can crash.

pxi

• Could be anything from a faulty cartridge to damaged internal components, but will almost always be some type of hardware issue.

qtm/cam

• The camera's hardware is damaged or dead.
  • To fix, replace the camera with a new one. To avoid the error until then, disconnect the camera or avoid using anything that activates the camera.