After many requests we finally have stock of the SaveMii for Wii, these little devices that plug into the GameCube memory card slot on the Wii can recover a Wii console that has been bricked by a bad firmware update, for example, you have a PAL console that was running 3.1e and you accidently accepted a Wii system update from a NTSC game, this would have either completely or semi bricked your Wii console, the semi-brick is where you can still play your backups, but access to the Wii system settings menu is no longer accessible and your original PAL games will no longer work, a full brick is where the console will no longer boot. This is where the SaveMii device comes in, it will plug into the front of your Wii and boot the console to a mode where you can insert a game that has a PAL system update and you will be able to run that update to un-brick the console. Just note though that the game you are trying to use for the un-bricking process must have a higher firmware on it than the one that bricked your console, for example, the firmware that bricked your machine was 3.2u, you now need to obtain an original PAL game that has a 3.3e firmware on it to un-brick the console, it works the other way around for NTSC systems, if your console was bricked by a 3.2e PAL firmware, you will need an original NTSC game that has 3.3u firmware on it to un-brick the machine.
The SaveMii can un-brick most consoles, but there is still one of two that are bricked in such a way where the SaveMii won’t work, or if your console was bricked by the latest firmware 3.4, you will have to wait for a game with v3.5 firmware to be released before you will be able to attempt to un-brick the console. Still the SaveMii is your best chance at un-bricking your console and is a worthy investment for installers that would possibly see a few bricked Wii’s in their time and having one of these SaveMii tools lying around could come in very handy. Below is some text from the official SaveMii website that explains about the product a little more.
When powered on your Wii displays nothing but an error message, or nothing at all. We may have just the solution for your problem. There's a good chance a nifty little piece of hardware can allow you to fix your system, we call it the SaveMii. Most Wii “bricks” are the result of poor error checking or bugs in the Wii's System Menu. For example, if you have installed a system update off a wrong region's disk, the System Menu will only display an “Opera” error message and halt without running disks anymore, this is where the SaveMii will let you break out of this condition.
SaveMii allows you to skip most of the System Menu start-up process, especially the part that fails and halts the boot process. Instead, it causes the Wii to directly run software off a disk. Depending on the Wii's system version, and whether you’re Wii has a modchip installed, this allows you to either run a system update off a legit Wii disk, or a custom-made disk containing updates or homebrew tools.
SaveMii is a small dongle that is plugged into a Wii's GameCube memory card slot. It mimics a test interface that is believed to be used in Nintendo's own facilities dubbed “Waikiki” by Nintendo. When the System Menu is started and such a device is found, much of the System Menu's code is skipped. Instead, the System Menu checks the validity of the disk, runs an update from the inserted disk if present, and then tries to start a diagnostic also known as “auto boot” disk. This will allow updates from legit Wii disks to fix the system data. Or, if the Wii's system hasn't been updated to version 3.3 yet and is equipped with a modchip, even run custom-made disks containing updates or homebrew tools to modify the system.
SaveMii WebSite | Troubleshooting | User Guides