Canon LBP-800 Service Manual page 146

CHAPTER 4
2) Dirty or deformed transfer charging roller.
Action: Replace the transfer charging roller.
3) Defective photosensitive drum or developing cylinder
Action: Replace the cartridge.
II-12. Poor fixing
<Possible causes>
1) The nip width of the fixing unit is not within specification
Action: Replace the fixing pressure units.
2) Dirty pressure roller
Action: Clean the pressure roller. If the dirt cannot be removed, replace the pressure roller.
3) Scar(s) or dent(s) on the pressure roller surface
Action: Replace the pressure roller.
4) Scar(s) or dent(s) on the fixing film
Action: Replace the fixing film unit.
5) Deterioration of the thermistor
Action: Replace the fixing film unit.
II-13. Image distortion
<Possible causes>
1) Poor contact in the connectors on the laser/scanner unit
Action: Reconnect connector J208F on the engine controller PCB, or connector J801F and
J802F on the laser/scanner unit correctly.
2) Defective laser/scanner unit.
Action: Replace the laser/scanner unit.
3) Defective engine controller PCB
Action: Replace the engine controller PCB.
II-14. Faulty registration
<Possible causes>
1) Dirty or worn pick-up roller
Action: Clean the pick-up roller. Replace the roller if the dirt cannot be removed or the
roller is worn.
2) Dirty or worn feed roller
Action: Clean the feed roller. Replace the roller if the dirt cannot be removed or the roller
is worn.
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