"Turns off in a few seconds after turned on."에 답변Overheating problem. Worth a stripdown and reapply the heat sink compound to the CPU / heatsink.
"ceramic fuse is blowing in power supply board"에 답변Check for short after fuse. Voltage dependent device (if fitted, a blue flat disc size of 1p coin) will go short, as can the bridge rectifier or the smoothing capacitors.