Chapter 22-4When the 4-facet mirror rotates at a specific speed, the laser beam scans the photosensitive drum in keeping with themirror rotation, thus drawing static images on the photosensitive drum.Memo:BD FaultThe machine identifies a BD fault if it does not detect the /BDI signal within 0.1 sec after the scanner motor isforced to accelerate. It also detects a BD fault if it does not detect a specific interval of /BDI signals for 2 seccontinuously after the scanner motor has reached a specific revolution (number of rotations).Scanner FaultIf the machine does not detect the /BDI signal 1.4 sc after it has stopped forcing the scanner motor to accelerate,it extends the period of detection by 120 sec; if it still does not detect a specific interval of /BDI signals, itidentifies a scanner fault.BD ErrorThe machine identifies a BD error if it does not detect the /BDI signal at a specific interval while the /BDI signalis being generated. It, however, does not identify a BD error under the following condition:-the door is identified as being open within 0.2 sec after detection of a BD error.-a BD fault or a scanner fault is detected after a BD error has been identified.The laser/scanner unit contains parts that cannot be adjusted in the field. Do not attempt to disassemble the laser/scanner unit.
