Printer System: Black Spots - Konica Minolta bizhub 250 Service Manual

21. Image quality problem
21.3.12

Printer System: Black spots

A. Typical Faulty Images
B. Troubleshooting Procedure
Step Section
1 Paper Path
2 Imaging Unit
3 Fusing Unit
4 Imaging Unit
5
6
7 Erase Lamp
8
9 -
264
EDNord - Istedgade 37A - 9000 Aalborg - telefon 96333500
AA AA
Check Item
Toner is on the paper path.
Photo Conductor is dirty.
Fusing Rollers are dirty or scratched.
Comb Electrode contact terminal is dirty
or deformed.
Grid voltage contact terminal is dirty or
deformed.
Charge Neutralizing Sheet contact ter-
minal is dirty or deformed.
Erase Lamp is dirty.
Is there continuity across the Erase
Lamp?
The problem has been eliminated after
performing step 8.
Field Service Ver. 1.0 Aug. 2005
4036fs4029c0
Result
YES Clean.
YES Change Photo Conductor
Unit.
YES Change Fusing Unit.
YES Clean.
Change Photo Conductor
Unit.
YES Clean.
Change Photo Conductor
Unit.
YES Clean.
Change Photo Conductor
Unit.
YES Clean.
NO Change Erase Lamp.
NO Change Photo Conductor
Unit.
Change Developing Unit.
Change High Voltage
Unit.
Change Mechanical Con-
trol Board.
Action