Open the Cabinet, observation-filament is not lit. Measure the output voltage of the mains supply, 0V, 300V normal of the rectifier output, 5V power supply of the CPU is normal. Judging failure in the main power circuit, key elements were no exception but on closer inspection, load or short circuit to ground. Measurement of mains power thick film IC IC601 (DP308P) the PIN voltage, in addition to 1 foot, the other foot is 0V. After replacing IC601, trouble still. For detailed study of the machine drawings, IC602 boot foot (3 feet) is the starting voltage of 5V output switching power supply control. Direct measurement of microprocessor power T661 D663 anode voltage of 1 foot of add-ins, or 0V. Disconnect negative D663, measuring again: D663 cathode 17V. Almost o D663 cathode to ground resistance measurement ω, judge peripheral components to puncture or leakage. Upon closer inspection, leakage of electrolytic capacitor finds C663 breakdown. Replacing a 10 μg of F/50V model with the capacitor again power on, display normal startup, troubleshooting.