3DS:DS mode unbrick

The DS mode firmware used for backwards compatibility in a 3DS console can be made unusuable by several different things. This page lists the full usual set of troubleshooting steps to fix this issue.

The troubleshooting below should always be started at the first section. The troubleshooting will direct you to other sections as necessary.

This page assumes you have already tried TWLFix and both its alternate and manual variants without success. If you have not tried any of those pages already, do them now before starting the below instructions.

CFW Check

First, we will make sure your console has working CFW. This will help as it allows access to several useful homebrew tools, including GodMode9.

1. Power on your console while holding the SELECT button
   • If your console boots to the Luma3DS configuration menu, press START to save, then continue
   • If your console doesn't boot to the Luma3DS configuration menu, do the same without the SD card inserted
     • If your console does boot to the Luma3DS configuration menu, your SD card wasn't inserted correctly, re-insert it and try again
     • If your console doesn't boot to the Luma3DS configuration menu, you likely do not have Luma installed, and should install CFW before continuing as all but one of the fixes on this page require it
       • To make sure of this, hold SELECT+START+X+POWER for seven seconds while the console is powered off, then power off again, hold HOME, and then press POWER - if the notification LED lit up a color or the fastboot3DS menu appears, then you have working CFW but something is interfering with Luma. Join the Nintendo Homebrew Discord for more advanced help
       • If you do not have CFW and do not want to install it, you can still follow TWLFix if you can obtain homebrew access through a method on the guide

Troubleshooting

Section I - Prep Work

1. Follow Restoring / Updating CFW, then the "Updating GodMode9" and "Creating a NAND backup" sections on 3DS:GodMode9/Usage
   • Keep the NAND backup in your gm9/out folder if you have room, as it will be used if you need to do Section IV

Section II - Bizarre Edge Cases

1. Power off your console and insert the SD card into your computer
2. Open the file sd:/luma/config.ini in a text editor
3. Scroll down until you find the variables disable_arm11_exception_handlers and enable_dsi_external_filter
   • These variables should both be set to 0; if either of them are not, set them to 0 now
4. Exit the text editor, remove the SD card, and reinsert the SD card into your console
5. Power on your console
6. Open FBI, then go into Remote Install -> Scan QR code
7. Check whether the camera works, then press X and similarly check the other camera
   • If either camera causes an error or does not produce any output, your camera is likely bricked - this is known to cause DS mode issues. Disconnect the camera's cable ribbon and/or replace the camera entirely to fix this
8. Power off the console, then power on again while holding SELECT to access the Luma3DS configuration menu
9. If either of the following settings are enabled, disable them:
   • Enable loading external FIRMs and modules
   • Enable game patching
10. Either press START or select Save and exit, then attempt to open something that uses DS mode
    • If this works, look for and delete faulty patches in sd:/luma/sysmodules, sd:/luma/titles, and sd:/luma/twl_upscaling_filter.bin before turning any of their respective settings back on
    • If DS mode still crashes and the camera works, continue to Section III

Section III - NVRAM Analysis

Section III, Part I - Corruption Check

1. Open System Settings -> Other Settings -> Profile -> Nintendo DS Profile
   • If this crashes, continue to Part II of this section
   • If this does not crash, skip to Section IV

Section III, Part II - Restoration

1. Power off your console and insert the SD card into your computer
2. Download both NVRAMtool.3dsx and nvram.bin
3. Place both of these files in sd:/3ds
4. Reinsert the SD card into your console
5. Power on your console
6. Open the Homebrew Launcher, then open 3DS_NRAMtool
7. Once the app loads, press B, wait one second, and then press X
8. Press START, then exit out of the Homebrew Launcher
9. Reboot your console and then attempt to open the Nintendo DS Profile again
   • If the DS Profile still crashes, continue to Part III of this section
   • If the DS Profile does not crash, attempt to open something that uses DS mode (the DS Profile only uses NVRAM, not DS mode)
     • If DS mode still crashes, skip to Section IV

Section III, Part III - ctrcheck

1. Follow the instructions on the ctrcheck page
2. If you did not get Critical: NVRAM is inaccessible, then reboot after trying all other applicable fixes
3. Attempt to open something that uses DS mode
   • If this still crashes, continue to Section IV

Section IV - TinyFormat

1. Power off your console and insert the SD card into your computer
2. If your NAND backup from Section I is not already on your SD card, copy it to gm9/out now
3. Download TinyFormat (the .zip that is not the source code) and extract it
4. Copy TinyFormat.3dsx from 3ds/TinyFormat inside the zip, and paste it into sd:/3ds
5. Reinsert the SD card into your console
6. Power on your console
7. Go into the Homebrew Launcher, then open TinyFormat.3dsx
8. Press Y to start the format
9. your console will eventually load to initial setup - this is intended
10. Go through initial setup until you reach the HOME Menu
    • If you cannot complete initial setup for some reason, you may be able to bypass it using 2DSaver
11. Attempt to open something that uses DS mode
    • If this still crashes, restore your NAND backup and then continue to Section V

Section V - 3ds_hw_test

1. Power off your console and insert the SD card into your computer
2. Download 3ds_hw_test.zip and extract 3ds_hw_test.firm from it
3. Place this file in sd:/luma/payloads on the SD card
4. Reinsert the SD card into your console
5. Hold START, and while holding START power on the console
6. Select 3ds_hw_test
7. Press any button to start the test
8. The test will take up to 45 minutes - when it's done, press any button to turn it off
9. The file HWTEST.LOG will have been created on the SD root - open this file in a text editor
   • GodMode9 will work for this
10. Scroll down to the end and look at the number of errors
    • If this number is more than 0, your console's RAM is dying and you need to replace the motherboard

If the above number of errors is zero, you have now exhausted all of the conventional fixes. Go to the Nintendo Homebrew Discord, ask for help, and mention that you've tried this page already.