Display shows character of stroke, and kept flashing, can't do anything. Electricity observation, found that just boot screen display is normal, when copying or received, sent the manuscripts appeared the fault phenomenon. Open the machine, the display both normal and abnormal test + 24 v voltage stability is normal, thus judge fault in DC - DC conversion circuit. When failure occurs, test the + 5 V voltage fluctuations between + 2.8 V, 5 V, + 5 V voltage regulator circuit is abnormal. In turn Q461, D461, C472, L461 related components, found L461 has been damaged. Processing methods: replacement for the same model L461 after commissioning, troubleshooting.dfTservice manual download site