Analysis of a bad line scan circuit elements; + B voltage is too high; protection circuit malfunction undesirable elements; poor performing a switching power supply switching power supply components or thick block of IC802. Check around these ideas, first disconnect the + B voltage, connected load 100W bulb fraud monitoring + B voltage, power lamp will flash, + B voltage of 115V and slowly dropped to 0V, to prove fault in the switching power supply. Power, measured + B voltage is 0V, IC8021 pin is 300V, the other legs are 0V, it is clear that the power switch is not vibrating. Suspected adverse IC802 performance, fault still try to change IC802. IC802 scrutinize external components shown in the drawings, particularly electrolytic capacitors, found around wet C813, C813 welded under the electrolyte overflow detection, troubleshooting, replacement C813.cpXservice manual download site