Xbox 360:JTAG

The JTAG (aka SMC) hack was the first permanent modification that allows you to run unsigned code, mods, game backups, and homebrew on your phat console. The hack relies on vulnerabilities in the CB bootloader, which are only present on dashboards 7371 and lower. If you are on a higher dashboard, take a look at the recommended exploit chart and see what hack is right for you.

Note that this guide is a condensation of multiple JTAG guides, most notably the oblivioncth's Xbox 360 Ultimate Exploit Guide, Xecuter's JTAG guide , M AzeeM K's Alternate JTAG guide , X-Splinter's Matrix USB Flasher guide , as well as personal experience.

While it's recommended to read through this guide in its entirety, a video guide for JTAG can be found on MrMario2011's channel.

Note that JTAG does not support Slim/E motherboards.

Requirements
Below are the requirements to JTAG your Xbox 360. It's recommended to read ahead and choose the NAND dumping method and JTAG-specific wiring method that's right for you, as you will need more equipment or a NAND programmer depending on the method you choose.

To check if your console is exploitable, you must have:


 * 1) A fat console (Xenon, Zephyr, Falcon, Opus, or Jasper model). You can look at the back of your console and check the motherboard identification chart to find out what model you have.
 * 2) * If you have a Jasper, determine whether if there is Memory Unit built in. If it has 214MB of storage, it's a 256MB NAND. If it has 451MB of storage, it is a 512MB NAND.
 * 3) Your console on dashboard 7371 or lower. If you are on the original blades dashboard, that is sufficient. Otherwise, you can check this by navigating to Settings > Console Settings > Hover over System Info. Your dashboard version will be shown in the top right in the form 2.0.xxxxx.0, where xxxxx is your dashboard version.
 * 4) * If it is on dashboard 7371, the system may not be JTAGable. You can only find out by dumping your NAND.
 * 5) Soldering experience. The Xbox 360 is not a good place to learn to solder. Regardless of which dumping method you choose, you will need a soldering iron, solder, and flux.

Equipment Needed

 * A soldering iron, solder, flux, and Isopropyl alcohol with cotton swabs
 * Specific recommendatons can be found on this page
 * 28-30 AWG Wire (Solid core recommended)
 * Two 1N914/4148 switching diodes (Only on Xenon)
 * Two 10K Ohm 1/2W or 1/4W resistors with two 2N3904 transistors (Only with Boxxdr on Non-Xenon)
 * Wire Insulation (kapton tape, electrical tape, heatshrink, etc.) for the diodes
 * A PC running Windows Vista or later
 * J-Runner with Extras
 * Any compatible NAND Programmer (Listed below)
 * NAND Backup with XeLL written to the console (Listed below)

Reading your NAND
There are six different methods to making a dump of your NAND chip: xFlasher 360, Nand-X, JR Programmer, PicoFlasher, Matrix USB NAND Flasher, or a LPT cable. Consider the pros and cons below and choose the method that’s right for you. Once you have decided on a method, select the guide below and follow it to get a NAND dump, patch the dump, and write the dump to your motherboard. Once you’ve successfully backed up your NAND and wrote XeLL to it, continue to the next section.

Tutorial for backing up and writing XeLL to the NAND

JTAG-Specific Wiring
Choose the guide that pertains to you:

Xenon Method

 * This is the only method for Xenon motherboards. Do not use it if you have a non-Xenon motherboard.

Boxxdr Method

 * This method is for Zephyr, Opus, Falcon, or Jasper motherboards. This method may disable 5.1 audio output.

Boxxdr Method + Open_Tray

 * Use this method if the Boxxdr method doesn't boot, you receive E79 errors, or you have issues with HDMI. This method may cause your DVD drive to eject on bootup. Also, your console will reboot instead of shutting down if you turn off the console while a controller is charging via USB.

Decrypting the NAND
Once you have successfully obtained your CPU key, we can build an XeBuild image, which is a modified NAND built specifically for your console.
 * If you want to use J-Runner with the console connected to LAN to get the CPU key, enter the IP address XeLL gives you into the lower right of the app. You can then click  and XeLL will automatically decrypt the retail NAND dump you backed up earlier.
 * If you want to use XeLL's web page to get the CPU key, enter the Xbox's IP address in your preferred web browser. You will see information about the console, and the CPU key can be easily copy and pasted from this web page.
 * If you didn't have access to an ethernet cable to plug the Xbox into a PC or LAN, you can manually type the CPU key into J-Runner in order to decrypt your original NAND dump.

Writing a New NAND Image (NAND Flasher)

 * 1) Power down the console, and connect your programmer to the motherboard and computer.
 * 2) *If you are using an xFlasher, ensure the switch is set to.
 * 3) Open J-Runner and select  next to the Load Source field and either select your nanddump1.bin or nanddump2.bin if not already selected. In the upper right corner of the window, select the dashboard version you chose for the patched dump that you wrote to the motherboard and make sure that the   radio button is selected.
 * 4) *If you have a non-Xenon console, the  checkbox should be enabled.
 * 5) Click "Create XeBuild Image". This will take a few moments.
 * 6) Click "Write NAND".
 * 7) Disconnect your programmer when the process completes, and check if the console boots to the Microsoft dashboard. If it successfully boots to the dashboard, it is an indication that you've successfully hacked your console.
 * 8) * You may want to leave your Xbox 360 disassembled so that you can:
 * 9) ** ...disable the eFuse-blowing circuit so you can't accidentally install official updates on your console.
 * 10) ** ...check what temperatures it's running at so you can judge if you need to replace the thermal paste to avoid overly loud fans and/or overheating issues.
 * 11) Remove your NAND programmer wires and clean the points. Clean all flux off the board, allow it to dry, and test it once more before re-assembling. You're now free to install XEXMenu (instructions in section below).

Writing a New NAND Image (XeLL)

 * 1) Open J-Runner and select  next to the Load Source field and either select your nanddump1.bin or nanddump2.bin if not already selected. In the upper right corner of the window, select the dashboard version you chose for the patched dump that you wrote to the motherboard and make sure that the   radio button is selected.
 * 2) *If you have a non-Xenon console, the  checkbox should be enabled.
 * 3) Click "Create XeBuild Image". This will take a few moments.
 * 4) Copy updflash.bin to a FAT32 formatted USB storage device and plug it into your powered-off console. Turn on your console and it will boot into XeLL and begin flashing your NAND. Once it has finished, it will power off your console. Turn it back on, and it should boot to the Microsoft dashboard, which is an indication that you've successfully hacked your console.
 * 5) * You may want to leave your Xbox 360 disassembled so that you can:
 * 6) ** ...disable the eFuse-blowing circuit so you can't accidentally install official updates on your console.
 * 7) ** ...check what temperatures it's running at so you can judge if you need to replace the thermal paste to avoid overly loud fans and/or overheating issues.
 * 8) Remove your NAND programmer wires (if they are still attached) and clean the points. Clean all flux off the board, allow it to dry, and test it once more before re-assembling. You're now free to install XEXMenu (instructions in section below).

Installing XeXMenu

 * 1) Plug a flash drive into your Xbox 360 and navigate to Console Settings > Storage. Select the flash drive and allow it to format the flash drive as a system drive.
 * 2) Extract the `CODE9999` folder from the XeXMenu 1.2 rar to your Desktop.
 * 3) Plug the flash drive into your PC. Open Xplorer360 and select Drive > Open > Harddrive or Memcard. On the left-hand side, select Partition 3, then right-click the Content folder, select "New Folder", and name it `0000000000000000` (16 zeroes). Open the new folder, then drag the `CODE9999` folder into it.
 * 4) Select Drive > Close, then close Xplorer360. Safely eject your flash drive and plug it into your Xbox 360. Navigate to the Demos section of your dashboard, and it should list XeXMenu there. Select it to launch it.
 * 5) * You can install XeXMenu to your hard drive by going to Console Settings > Storage, and copying it from your flash drive to the hard drive.

From here, you can install any homebrew or mods that you want. See this page for a list of recommended modifications and applications to install.