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6-21
[ 5 ] Print-image related
If the received or sent image has any problem, first make a copy with the facsimile equipment.
If the copied image is normal, the problem may be due to the remote terminal; if it is abnormal,
proceed to the following checks:
Trouble
Action to be taken
(1) Completely blank
At the scanner
Check the following components:
- CIS harness
- Main PCB
- CIS unit
At the printer side
Clean the high-voltage contacts for the developer roller on the
drum unit, main cover, and high-voltage power supply PCB.
(Contacts in the illustration given on page 6-28)
Clean the grounding contacts on the drum unit, main cover, and
high-voltage power supply PCB. (Contacts in the illustration
given on page 6-28)
Check that the grounding plate is sandwiched between the
contact plate and gear drive unit. (Refer to CHAPTER 4,
Subsection 4.1.21, page 4-36.)
Replace the toner cartridge.
Replace the drum unit.
Check the connection of the laser flat cable on the main PCB.
Replace the main PCB.
Replace the laser unit.
Replace the high-voltage power supply PCB.
(2) All black
At the scanner
Check the following components:
- CIS harness
- CIS unit
- Main PCB
At the printer side
Clean the high-voltage contacts for the grid and charger on the
drum unit, main cover, and high-voltage power supply PCB.
(Contacts and in the illustration given on page 6-28)
Clean the charger (corona wires) itself.
Check the connection of the laser flat cable on the main PCB.
Replace the drum unit.
Replace the high-voltage power supply PCB.
Replace the main PCB.
Summary of Contents for Laser MFC-4800
Page 5: ...CHAPTER 1 GENERAL DESCRIPTION ...
Page 16: ...CHAPTER 2 INSTALLATION ...
Page 21: ...CHAPTER 3 THEORY OF OPERATION ...
Page 23: ...3 1 3 1 OVERVIEW ...
Page 31: ...3 9 Location of Sensors and Actuators ...
Page 33: ...CHAPTER 4 DISASSEMBLY REASSEMBLY AND LUBRICATION ...
Page 39: ...4 4 Disassembly Order Flow ...
Page 44: ...4 9 6 Turn the ASF upside down then remove the registration sensor actuator ...
Page 86: ...4 48 2 Scanner drive unit 3 Separation roller ...
Page 87: ...4 49 4 Document feed roller ...
Page 88: ...CHAPTER 5 MAINTENANCE MODE ...
Page 95: ...5 6 Scanning Compensation Data List a b c d e ...
Page 102: ...5 13 Key Button Entry Order ...
Page 110: ...CHAPTER 6 ERROR INDICATION AND TROUBLESHOOTING ...
Page 140: ...FAX2800 FAX2900 FAX3800 MFC4800 FAX8070P MFC9030 MFC9070 Appendix 1 EEPROM Customizing Codes ...
Page 143: ...FAX2800 FAX2900 FAX3800 MFC4800 FAX8070P MFC9030 MFC9070 Appendix 2 Firmware Switches WSW ...
Page 190: ...A Main PCB 1 5 ...
Page 191: ...A Main PCB 2 5 ...
Page 192: ...A Main PCB 3 5 ...
Page 193: ...A Main PCB 4 5 ...
Page 194: ...A Main PCB 5 5 ...
Page 195: ...B NCU PCB U S A Canada ...
Page 196: ...B NCU PCB U K Norway Netherlands Finland Denmark Sweden ...
Page 197: ...B NCU PCB Germany France Belgium Switzerland Ireland Austria Spain Italy South Africa ...
Page 198: ...B NCU PCB Asia Oceania 1 2 ...
Page 200: ...C Control Panel PCB ...
Page 201: ...D Power Supply PCB 100 120V Low voltage power supply ...
Page 202: ...D Power Supply PCB 200 240V Low voltage power supply Europe ...
Page 203: ...D Power Supply PCB 200 240V Low voltage power supply Asia Oceania ...
Page 204: ...D Power Supply PCB High voltage power supply ...