
3–18
IMAGE FAULTS
Cause
Drum
cartridge
Drum drive
assembly
Transfer
charging
roller
Composite
power
supply PCB
Step
1
2
3
4
5
Checks
Is the drum cartridge installed?
Is the photosensitive drum rotating
during copying operation?
Is the transfer charging roller installed
securely?
Is electrical leakage noted on the
transfer charging roller?
Is the setting in service mode 105
(primary current indication) 10 µA or
less?
Remedy
Install the drum cartridge.
1. Check if the photosensi-
tive drum is rotating
smoothly.
2. Check the drum drive as-
sembly.
Install the transfer charging
roller securely.
Check the transfer charging
roller.
Replace the composite
power supply PCB.
Yes/No
NO
NO
NO
YES
YES
Cause
Composite
power
supply PCB
Step
1
2
3
Checks
Check according to “The scanning
lamp fails to turn ON.”
Does the pre-exposure lamp remain
ON during copying operation?
Is the setting of service mode No. 105
(primary current indication) 10 µA or
less?
Remedy
Does the scanning lamp
remain ON during copying
operation?
Check according to “The
pre-exposure lamp fails to
turn ON.”
Replace the composite
power supply PCB.
Yes/No
NO
NO
YES
21
The copy is blank.
22
The copy is solid black.
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 ...