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CHAPTER 4 TROUBLESHOOTING
Confidential
4-52
(I-16) Black spots
Possible cause
Step
Check
Result
Remedy
Ground
contacts
Drum unit
1
Are the spots at 94.2mm
intervals?
(The problem is not solved
after printing a few pages.)
Yes
1) If toner or glue
remains stuck, wipe it
off gently with a
cotton swab. (Refer
to
previous page.)
2) If the exposure drum
is scratched or
deteriorated
(exposed), replace
the drum unit.
Drum
connection
failure
2
Is the contact between the
drum unit and printer body
connected correctly?
No
Clean contact electrode
both on the drum unit
and in the printer body.
Fuser unit
3
Are the spots at 79mm
intervals?
(The problem is not solved
after printing a few pages.)
Yes
1) Check and clean the
heat roller with a cloth
dampened with
alcohol.
2) Replace the fuser
unit.
High-voltage
power supply
PCB failure
4
Is the problem solved after
replacing the high-voltage
power supply PCB?
Yes
Replace the high-voltage
power supply PCB.
User Check
(1) If the problem is not solved after printing a few pages, the drum unit may have
glue from label stock on the exposure drum surface. Refer to Step 1 in the table
below and
in the previous page.
(2) The drum unit may be damaged. Install a new drum unit.