Chapter 3 Disassembly/Reassembly - Brother HL-5440D Service Manual

4.2.4 Duplex printing is not possible............................................................................. 2-58
4.2.5 Paper is curled .................................................................................................... 2-58
4.2.6 Only single surface is printed in duplex printing mode ........................................ 2-58
4.3 Troubleshooting for Image Defects.................................................................................... 2-59
4.3.1 Image defect examples ....................................................................................... 2-59
4.3.2 Troubleshooting according to image defect ........................................................ 2-60
4.4 Troubleshooting for Software Problems ............................................................................ 2-73
4.4.1 Cannot print data................................................................................................. 2-73
4.5 Troubleshooting for Network Problems ............................................................................. 2-74
4.5.1 Cannot print via network connection ................................................................... 2-74
4.5.2 Cannot connect to access point .......................................................................... 2-74
4.6 Troubleshooting for Control Panel Problems..................................................................... 2-75
4.6.1 Nothing is displayed on the LCD ......................................................................... 2-75
4.6.2 LEDs are not activated ........................................................................................ 2-75
4.6.3 Control panel is inoperable.................................................................................. 2-75
4.7 Troubleshooting for Toner and Drum Problems ................................................................ 2-76
4.7.1 New toner is not detected.................................................................................... 2-76
4.7.2 Cartridge error (toner cartridge cannot be detected)........................................... 2-76
4.7.3 Drum error ........................................................................................................... 2-76
4.8 Troubleshooting for Fuser Unit Problems .......................................................................... 2-77
4.8.1 Fuser unit failure.................................................................................................. 2-77
4.9 Troubleshooting for Laser Unit Problems .......................................................................... 2-78
4.9.1 Laser unit failure.................................................................................................. 2-78
4.10 Troubleshooting for PCB Problems ................................................................................... 2-79
4.10.1 Main PCB failure ................................................................................................. 2-79
4.10.2 High-voltage power supply PCB failure............................................................... 2-79
4.10.3 Low-voltage power supply PCB failure................................................................ 2-79
4.11 Troubleshooting for Other Problems.................................................................................. 2-80
4.11.1 Machine is not turned ON.................................................................................... 2-80
4.11.2 Main fan does not rotate...................................................................................... 2-80
4.11.3 Main motor failure................................................................................................ 2-80
4.11.4 Unusual noise is generated from the machine .................................................... 2-80
CHAPTER 3 DISASSEMBLY/REASSEMBLY
1. SAFETY PRECAUTIONS............................................................................................................. 3-1
2. PACKING ..................................................................................................................................... 3-2
3. SCREW CATALOGUE................................................................................................................. 3-3
4. SCREW TORQUE LIST ............................................................................................................... 3-4
5. LUBRICATION ............................................................................................................................. 3-6
6. OVERVIEW OF GEARS............................................................................................................... 3-7
7. HARNESS ROUTING................................................................................................................... 3-9
8. DISASSEMBLY FLOW CHART................................................................................................. 3-14
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