CHAPTER 6 TROUBLESHOOTING
6-24
6. TROUBLESHOOTING OF THE CONTROL PANEL
L-1
Nothing is displayed on the LCD.
User Check
(1) Verify if the power switch is turned off.
Possible cause
Step
Check
Result
Remedy
Connection
between main
PCB, and
control panel
PCB
1
Main PCB and control panel
PCB are properly connected.
No
Fix the connector properly.
Harness
between main
PCB, and
control panel
PCB
2
Harness wire is damaged.
Yes
Replace the harness with a
normal part.
Connection
between main
PCB and low-
voltage power
supply PCB
3
Main PCB and low-voltage
power supply PCB are
properly connected.
No
Fix the connection properly.
Harness
between main
PCB and low-
voltage power
supply PCB
4
Harness wire is damaged.
Yes
Replace the harness with a
normal part.
LCD 5
Replacement of LCD solves
the problem.
Yes
Replace the LCD with a
normal part.
Control panel
PCB
6
Replacement of control panel
PCB solves the problem.
Yes
Replace the control panel
PCB with a normal part.
Low-voltage
power supply
PCB
7
Replacement of low-voltage
power supply PCB solves the
problem.
Yes
Replace the low-voltage
power supply PCB with a
normal part.
Main PCB
8
Replacement of main PCB
solves the problem.
Yes
Replace the main PCB with
a normal part.
Summary of Contents for MFC-8220
Page 60: ...MFC 8220 SERVICE MANUAL 3 5 1 3 4 ROM Fig 3 6 ...
Page 244: ...CHAPTER 7 MAINTENANCE MODE 7 6 Fig 7 2 a b c d e f g h i j ...
Page 312: ...APPENDIX 4 CIRCUIT DIAGRAM A 48 Appendix 4 1 Main PCB Circuit Diagram 1 6 ...
Page 313: ...MFC 8220 SERVICE MANUAL A 49 Appendix 4 2 Main PCB Circuit Diagram 2 6 ...
Page 314: ...APPENDIX 4 CIRCUIT DIAGRAM A 50 Appendix 4 3 Main PCB Circuit Diagram 3 6 ...
Page 315: ...MFC 8220 SERVICE MANUAL A 51 Appendix 4 4 Main PCB Circuit Diagram 4 6 ...
Page 316: ...APPENDIX 4 CIRCUIT DIAGRAM A 52 Appendix 4 5 Main PCB Circuit Diagram 5 6 ...
Page 317: ...MFC 8220 SERVICE MANUAL A 53 Appendix 4 6 Main PCB Circuit Diagram 6 6 ...
Page 318: ...APPENDIX 4 CIRCUIT DIAGRAM A 54 Appendix 4 7 Engine PCB Circuit Diagram 1 2 ...
Page 319: ...MFC 8220 SERVICE MANUAL A 55 Appendix 4 8 Engine PCB Circuit Diagram 2 2 ...
Page 320: ...APPENDIX 4 CIRCUIT DIAGRAM A 56 Appendix 4 9 NCU PCB Circuit Diagram Europe ...
Page 321: ...MFC 8220 SERVICE MANUAL A 57 Appendix 4 10 NCU PCB Circuit Diagram U S A ...
Page 322: ...APPENDIX 4 CIRCUIT DIAGRAM A 58 Appendix 4 11 Control Panel PCB Circuit Diagram ...
Page 323: ...MFC 8220 SERVICE MANUAL A 59 Appendix 4 12 Low voltage Power Supply PCB Circuit Diagram ...
Page 325: ...MFC 8220 SERVICE MANUAL A 61 Appendix 4 14 High voltage Power Supply PCB Circuit Diagram 200V ...
Page 326: ...APPENDIX 4 CIRCUIT DIAGRAM A 62 Appendix 4 15 Back Light PCB Circuit Diagram ...
Page 328: ...February 04 SM FAX026 6 8X5913 Printed in Japan ...