hi, here is my issue, i hope some one can help me to recover my wii :-(

i had 4.0 softmodded wii without modchip, i perform a downgrade to 3.2 and worked fine, placed a mon welded modchip on my wii (the one thats only atacched by flex)
after that i did de Guitar Hero 5 disc update..... and thats it i bricked my wii
black screen when i shut it on
i can turn it on with wii mote
i have bootmii as boot2 so i can get to the HBC , i accidentally detete IOS 249 and now i cant even perform rebooter.....
what are my chances and what do you recommend to recover my wii?