This machine according to the "POWER" key "secondary" boot, lights flashing and relay suck and release the voice of the measurement of switching POWER supply output voltage fluctuate, measure the microprocessor IC1213 6 feet (CPROTECT/protection) high level voltage, judgment is fracture in the microprocessor protection circuit into protection state. Disconnect + B and output load circuit, dummy load after boot, measuring voltage + B returned to normal, and no longer protected. Analysis is a + B load circuit circuit leakage problems.  JjLservice manual download site
 JjLservice manual download site
Focus detection line output circuit, no obvious fault; By disconnect + B road load circuit, the method of turning experiment was carried out, when the operation when the drive circuit of power supply and switch on is no longer protected. To test the line drive circuit Q590, between the collector and emitter of around 1 k Ω leakage resistance. After replacing Q590, troubleshooting.JjLservice manual download site