Developing Assembly - Canon imageRUNNER ADVANCE 4551i Service Manual

2. If there is Drum Unit Memory, judge whether the Drum Unit is new or old (has been replaced or not).
Drum Unit New/Old Sensor
Related Alarm Codes
• Drum Unit (Bk) replacement completion alarm: 43-0073
• Drum memory tag detection error (Bk): 09-0013

Developing Assembly

The developing assembly mainly consists of the developing cylinder, developing blade, toner agitation plate, and toner feed screw,
and driven by the main motor (M1) and developing cylinder clutch (CL1).
The toner supplied from the toner cartridge is fed into the developing assembly by the toner feed screw and toner agitation plate.
The toner presence/absence in the developing assembly is detected by the developing assembly toner sensor (S25) which is a
magnetic permeability sensor.
UN2
DC Controller PCB
Information specific to the drum
Drum Unit Memory
94
2. Technology