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6-17
6.2 TROUBLESHOOTING
6.2.1 Introduction
This section gives the service personnel some of the troubleshooting procedures to be followed if
an error or malfunction occurs with the facsimile equipment. It is impossible to anticipate all of the
possible problems which may occur in future and determine the troubleshooting procedures, so this
section covers some sample problems. However, those samples will help service personnel
pinpoint and repair other defective elements if he/she analyzes and examines them well.
6.2.2 Precautions
Be sure to observe the following to prevent the secondary troubles from happening:
(1) Always unplug the AC power cord from the outlet when removing the covers and PCBs,
adjusting the mechanisms, or conducting continuity testing with a circuit tester.
(2) When disconnecting the connectors, do not pull the lead wires but hold the connector
housings.
(3)
Before handling the PCBs, touch a metal portion of the machine to discharge static
electricity charged in your body.
When repairing the PCBs, handle them with extra care.
After repairing the defective section, be sure to check again if the repaired section works correctly.
Also record the troubleshooting procedure so that it would be of use for future trouble occurrence.
6.2.3 Checking prior to Troubleshooting
Prior to proceeding to the troubleshooting procedures given in Subsection 6.2.4, make the
following initial checks:
Environmental conditions
Check that:
(1) The machine is placed on a flat, firm surface.
(2) The machine is used in a clean environment at or near normal room temperature (10
°
C to
32.5
°
C) with normal relative humidity (20 to 80%).
(3) The machine is not subjected to rapid change of the ambient temperature. (Moving the
machine from a cold place to warm place will cause condensation inside the machine. If it
takes place, leave the machine in the warm place for approx. two hours before turning on the
power.) Powering on the machine with dew condensation will result in damaged electronic
devices.
(4) The machine is not exposed to direct sunlight or harmful gases.
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 ...