I suspect BMC is corrupted on your system due to power outage. You can try flashing BMC using DOS bootable image. Latest BMC available in below link and you can use "PE1425BmcA08.exe" from below link. Instructions to flash is available on "Installation instructions" section of same link [URL] 
Heya everyone, I was performing maintenance on some of my older homelab equipment and during a BMC update on my PowerEdge SC1425, I had a power outage at home. After power was restored I was greeted by "Baseboard Management Controller communication failure" and the fans were going at full tilt. Is there a way for me to fix the BMC?    Thanks in Advance, Lu
SC1425 BMC communication failure