There are two ways to unbrick a fully bricked wii:
1. If you had bootmii as boot2 installed, you can use it to restore a back-up, or if you don't have one you can use this guide: Fully Brick, Bootmii/boot2 installed but No Nand Backup? Solution Here!
2. If you don't have bootmii as boot2 installed, your only option is to use a NAND programmer to restore a back-up. If you don't have a NAND programmer, then you can send it to one of the forum members who do have one. If you don't have a back-up it is the end of the story.
Those are the only two options.