Boot Q901 examination revealed the power main vibration tube and power supply IC have been damaged, change new boot found after 110 v mains voltage cannot be established, the multimeter measuring ac voltage of 320 v or so after the rectification, the voltage drops slowly after shutdown, the power of the shows that this machine can't start up, resistance capacitance and tested according to the power part of the diode are not found the problem, after careful examination, C905 will be removed the measurement capacity of only 2.9 UF, the original capacity should be 4.7 UF, the capacitance change new, troubleshooting.v6Tservice manual download site