CHAPTER 4 TROUBLESHOOTING IMAGE FAULTS/MALFUNCTIONS4-233.20 The copy has inadequate sharpness.Copyboard glass1) Is there oil or the like on the copyboard glass? Is there foreign matter onthe copyboard glass stay?YES: Clean the copyboard glass.Scanner2) Clean the scanning lamp, reflecting plate, mirrors, and lenses. Is theproblem corrected?YES: End.Mirror (position)3) Is the horizontal reproduction ratio in Direct as indicated?NO: Adjust the position of the No. 1 mirror an the No. 2 mirror.Developing bias4) Are the connection and the electrical continuity of the high-voltage forthe developing bias normal? (The resistance of the cable for the developingbias and the resistance between the terminal of the composite power supplyPCB and the terminal on the developing assembly is about 10 kΩ.)NO: Check the connection; and replace the cable. If the problem is stillnot corrected,1. Replace the composite power supply PCB2. Replace the DC controller PCB.Drum unit, Transfer charging system5) Try replacing the drum unit. Is the problem corrected?YES: End.NO: Check the transfer charging system.
