MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
6-39
I-5
Dirt on the back of paper
Possible cause
Step
Check
Result
Remedy
Fixing unit dirty
1
Is the pressure roller dirty?
Is any other area in the
machine dirty?
Yes
Clean the pressure roller
referring to the following
procedure.
Dirt in the drum
unit
2
Is the transfer roller dirty?
Is the problem solved after
replacing the drum unit?
Yes
Replace the drum unit
No
Replace the high-voltage power
supply PCB.
NOTE:
This problem may disappear after printing approximately 10 pages of completely blank sheets.
How to clean the pressure roller
Clean the pressure roller as follows
(1) Set ten or more sheets of paper in the paper tray.
(2) Check the absence of paper in the ADF and on the scanner glass.
(3) Press
Copy
button to copy and repeat it five times.
(4) Check whether any stain are observed on the back of paper or not.
Summary of Contents for DCP 8040 - B/W Laser - All-in-One
Page 272: ...CHAPTER 7 MAINTENANCE MODE 7 6 Fig 7 3 l m a b c d e f g h i j k ...
Page 343: ...APPENDIX 4 CIRCUIT DIAGRAMS A 50 Appendix 4 1 Main PCB Circuit Diagram 1 7 ...
Page 345: ...APPENDIX 4 CIRCUIT DIAGRAMS A 52 Appendix 4 3 Main PCB Circuit Diagram 3 7 ...
Page 347: ...APPENDIX 4 CIRCUIT DIAGRAMS A 54 Appendix 4 5 Main PCB Circuit Diagram 5 7 ...
Page 349: ...APPENDIX 4 CIRCUIT DIAGRAMS A 56 Appendix 4 7 Main PCB Circuit Diagram 7 7 ...
Page 351: ...APPENDIX 4 CIRCUIT DIAGRAMS A 58 Appendix 4 9 Engine PCB Circuit Diagram 1 2 ...
Page 353: ...APPENDIX 4 CIRCUIT DIAGRAMS A 60 Appendix 4 11 NCU PCB Circuit Diagram U S A ...
Page 355: ...APPENDIX 4 CIRCUIT DIAGRAMS A 62 Appendix 4 13 NCU PCB Circuit Diagram Asia ...
Page 357: ...APPENDIX 4 CIRCUIT DIAGRAMS A 64 Appendix 4 15 Control Panel PCB Circuit Diagram ...
Page 362: ...April 04 SM FAX027 1 8C5903 Printed in Japan ...
