
MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
6-47
I-16 Black
spots
Possible cause
Step
Check
Result
Remedy
Ground
contacts
Drum unit
1
Are the spots at 94mm
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 photosensitive
drum is scratched or
deteriorated
(exposed), replace
the drum unit.
Drum
connection
failure
2
Is the contact between the
drum unit and machine
connected correctly?
No
Clean contact electrode
both on the drum unit
and in the machine.
Fixing 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 fixing
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 photosensitive 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.
Содержание DCP-8040
Страница 146: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 64 5 Remove the shutter arm C Fig 4 115 Shutter arm C Frame L ...
Страница 276: ...CHAPTER 7 MAINTENANCE MODE 7 6 Fig 7 3 l m a b c d e f g h i j k ...
Страница 347: ...APPENDIX 4 CIRCUIT DIAGRAMS A 50 Appendix 4 1 Main PCB Circuit Diagram 1 7 ...
Страница 348: ...MFC 8440 8840D 8840DN DCP 8040 8045D 8045DN SERVICE MANUAL A 51 Appendix 4 2 Main PCB Circuit Diagram 2 7 ...
Страница 349: ...APPENDIX 4 CIRCUIT DIAGRAMS A 52 Appendix 4 3 Main PCB Circuit Diagram 3 7 ...
Страница 350: ...MFC 8440 8840D 8840DN DCP 8040 8045D 8045DN SERVICE MANUAL A 53 Appendix 4 4 Main PCB Circuit Diagram 4 7 ...
Страница 351: ...APPENDIX 4 CIRCUIT DIAGRAMS A 54 Appendix 4 5 Main PCB Circuit Diagram 5 7 ...
Страница 352: ...MFC 8440 8840D 8840DN DCP 8040 8045D 8045DN SERVICE MANUAL A 55 Appendix 4 6 Main PCB Circuit Diagram 6 7 ...
Страница 353: ...APPENDIX 4 CIRCUIT DIAGRAMS A 56 Appendix 4 7 Main PCB Circuit Diagram 7 7 ...
Страница 354: ...MFC 8440 8840D 8840DN DCP 8040 8045D 8045DN SERVICE MANUAL A 57 Appendix 4 8 Driver PCB Circuit Diagram ...
Страница 355: ...APPENDIX 4 CIRCUIT DIAGRAMS A 58 Appendix 4 9 Engine PCB Circuit Diagram 1 2 ...
Страница 356: ...MFC 8440 8840D 8840DN DCP 8040 8045D 8045DN SERVICE MANUAL A 59 Appendix 4 10 Engine PCB Circuit Diagram 2 2 ...
Страница 357: ...APPENDIX 4 CIRCUIT DIAGRAMS A 60 Appendix 4 11 NCU PCB Circuit Diagram U S A ...
Страница 358: ...MFC 8440 8840D 8840DN DCP 8040 8045D 8045DN SERVICE MANUAL A 61 Appendix 4 12 NCU PCB Circuit Diagram Europe ...
Страница 359: ...APPENDIX 4 CIRCUIT DIAGRAMS A 62 Appendix 4 13 NCU PCB Circuit Diagram Asia ...
Страница 360: ...MFC 8440 8840D 8840DN DCP 8040 8045D 8045DN SERVICE MANUAL A 63 Appendix 4 14 NCU PCB Circuit Diagram Oceania ...
Страница 361: ...APPENDIX 4 CIRCUIT DIAGRAMS A 64 Appendix 4 15 Control Panel PCB Circuit Diagram ...
Страница 363: ...APPENDIX 4 CIRCUIT DIAGRAMS A 66 Appendix 4 17 Low voltage Power Supply PCB Circuit Diagram 100V ...
Страница 365: ...APPENDIX 4 CIRCUIT DIAGRAMS A 68 Appendix 4 19 High voltage Power Supply PCB Circuit Diagram 100V ...
Страница 367: ...April 04 SM FAX027 5 8C5903 Printed in Japan ...