3–12
IMAGE FAULTS
Cause
Toner
Photosensi-
tive drum
Primary
charging
roller
Transfer
charging
roller
Copy paper
Scanner rail,
Scanner
cable
Step
1
2
3
4
5
6
7
8
9
10
Checks
Remove the developing assembly,
and shake it several times. Is the
problem corrected?
Is the problem noted at intervals of
about 9.4 cm? (scratches on photo-
sensitive drum)
Is the problem noted at intervals of
about 5.1 cm?
Execute service mode No. 402
(primary charging roller cleaning). Is
the problem corrected?
Execute service mode No. 403
(transfer roller cleaning). Is the
problem corrected?
Is the problem noted at intervals of
about 5.1 cm?
Is there dirt, crack, or scratches on the
transfer charging roller?
Are the position and the condition of
the transfer charging roller pressure
spring normal?
Try fresh copy paper. Is the problem
corrected?
Is the problem noted at the same
location on all copies?
Yes/No
YES
YES
YES
YES
YES
YES
YES
NO
YES
YES
Remedy
The toner may be inad-
equate; advise the user.
1. Clean the drum.
2. If the drum has scratches,
replace the drum car-
tridge.
Check the primary charging
roller for scratches and dirt.
End.
End.
Check the transfer charging
roller for scratches and dirt.
Replace the transfer charg-
ing roller.
Correct or replace the spring.
The copy paper may be
moist; advise the user on the
correct method of storing
paper.
1. Check the scanner rail for
foreign matter.
2. Adjust the scanner cable
tension.
12
The copy has white spots (horizontal).
Summary of Contents for NP6621
Page 4: ...ii ...
Page 8: ...vi ...
Page 48: ...3 2 IMAGE FAULTS ...
Page 49: ...3 3 IMAGE FAULTS NOT USED ...
Page 50: ...3 4 IMAGE FAULTS B Image Fault Samples not available ...
Page 80: ...4 16 TROUBLESHOOTING MALFUNCTIONS ...
Page 134: ...A 4 APPENDIX ...
Page 135: ...A 5 APPENDIX C GENERAL CIRCUIT DIAGRAM not available ...
Page 136: ...A 6 APPENDIX ...
Page 144: ...A 14 APPENDIX ...
