Brother MFC-8440 User manual


SERVICE MANUAL
MODEL: MFC8440/8840D/8840DN
DCP8040/8045D/8045DN
Read this manual thoroughly before maintenance work.
Keep this manual in a convenient place for quick and easy reference at all times.
fineline6

MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
PREFACE
This publication is a Service Manual covering the specifications, construction, theory of
operation, and maintenance of the Brother machine. It includes information required for field
troubleshooting and repair--disassembly, reassembly, and lubrication--so that service
personnel will be able to understand machine function, to rapidly repair the machine and order
any necessary spare parts.
To perform appropriate maintenance so that the machine is always in best condition for the
customer, the service personnel must adequately understand and apply this manual.
This manual is made up of six chapters and appendices.
CHAPTER 1: GENERAL
CHAPTER 2: INSTALLATION AND BASIC OPERATION
CHAPTER 3: THEORY OF OPERATION
CHAPTER 4: DISASSEMBLY AND RE-ASSEMBLY
CHAPTER 5: PERIODIC MAINTENANCE
CHAPTER 6: TROUBLESHOOTING
CHAPTER 7: MAINTENANCE MODE
APPENDIX 1: EEPROM CUSTOMIZING CODES
APPENDIX 2: INSTALLING THE UPDATE DATA
APPENDIX 3: FIRMWARE SWITCHS (WSW)
APPENDIX 4: CIRCUIT DIAGRAMS
Information in this manual is subject to change due to improvement or redesign of the product.
All relevant information in such cases will be supplied in service information bulletins
(Technical Information).
A thorough understanding of this printer, based on information in this service manual and
service information bulletins, is required for maintaining its print quality performance and for
improving the practical ability to find the cause of problems.
fineline6

TABLE OF CONTENTS
ii
TABLE OF CONTENTS
REGULATION............................................................................................ viii
SAFETY INFORMATION .............................................................................. x
CHAPTER 1 GENERAL...........................................................................1-1
1. OV ERVIEW ............................................................................................................ 1-1
2. SPEC IFICATIONS .................................................................................................. 1-3
2.1 G eneral.............................................................................................................................1-3
2.2 G eneral (Continued) .........................................................................................................1-3
2.3 Print Media ....................................................................................................................... 1-4
2.4 Copy ................................................................................................................................. 1-4
2.5 Fax .................................................................................................................................... 1-5
2.6 Sc anner ............................................................................................................................ 1-6
2.7 Printer ...............................................................................................................................1-6
2.8 Interf aces..........................................................................................................................1-7
2.9 Cons umable Items ........................................................................................................... 1-7
2.10 Network (LAN) Board (NC-9100h) ................................................................................... 1-7
2.11 Com puter Requirements .................................................................................................. 1-8
2.12 Paper ................................................................................................................................1-9
2.12.1 Type and size of paper........................................................................................................1-9
2.12.2 Recommended paper..........................................................................................................1-9
2.12.3 Paper capacity of the paper trays........................................................................................1-9
2.12.4 Paper specifications for each paper tray..........................................................................1-10
2.13 Printable Area................................................................................................................. 1-11
2.13.1 PCL5e/EPSON/IBM emulation..........................................................................................1-11
2.13.2 PCL6/BR-Script3 emulation ..............................................................................................1-14
2.14 Print Speeds with Various Settings ................................................................................ 1-15
2.15 Toner Cartridge Weight Information............................................................................... 1-15
3. SERIAL NO. DESCRIPTIONS .............................................................................. 1-16
CHAPTER 2 INSTALLATION AND BASIC OPERATION.......................2-1
1. CONDITIONS REQUIRED FOR INSTALLATION................................................... 2-1
1.1 Pow er Supply.................................................................................................................... 2-1
1.2 Env ironment .....................................................................................................................2-1
2. U NPACKING........................................................................................................... 2-2
3. INSTALL THE MACHINE........................................................................................ 2-3
3.1 For All Users.....................................................................................................................2-3
3.1.1 Install the Automatic Document Feed (ADF) support..........................................................2-4
3.1.2 Install the drum unit assembly.............................................................................................2-5
3.1.3 Load paper into the paper tray ............................................................................................2-6
3.1.4 Release the scanner lock....................................................................................................2-7
3.2 Installing the Driver & Software ........................................................................................ 2-8
3.2.1 For USB Interface Cable Users (For Windows® 98/98SE/Me/2000 Professional/XP) ........2-8
fineline6

MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
iii
3.2.2 For Parallel Interface Cable Users
(For Windows® 95/98/98SE/Me/2000 Professional/XP) ...................................................2-13
3.2.3 For Windows NT® Workstation Version 4.0 Users............................................................ 2-18
3.2.4 For Network Interface Cable Users
(For Windows® 95/98/98SE/Me/NT/2000 Professional/XP)..............................................2-20
3.2.5 For USB Interface Cable Users (For Mac® OS 8.6 to 9.2 Users) ......................................2-23
3.2.6 For USB Interface Cable Users (For Mac® OS X 10.1/10.2.1 or greater Users) ...............2-24
3.2.7 For Network Interface Cable Users (For Mac® OS 8.6 to 9.2 Users) ................................ 2-25
3.2.8 For Network Interface Cable Users (For Mac® OS X 10.1/10.2.1 or greater Users) .........2-26
CHAPTER 3 THEORY OF OPERATION.................................................3-1
1. E LECTRONICS ...................................................................................................... 3-1
1.1 General Block Diagram .................................................................................................... 3-1
1.2 Main PCB Block Diagram ................................................................................................. 3-2
1.3 Main PCB ......................................................................................................................... 3-3
1.3.1 CPU .....................................................................................................................................3-3
1.3.2 USB .....................................................................................................................................3-3
1.3.3 IEEE 1284 ...........................................................................................................................3-4
1.3.4 RO M....................................................................................................................................3-4
1.3.5 Flash ROM ..........................................................................................................................3-5
1.3.6 SDRAM ...............................................................................................................................3-5
1.3.7 O ptional RAM......................................................................................................................3-6
1.3.8 EEPRO M.............................................................................................................................3-7
1.3.9 Reset circuit ........................................................................................................................3-7
1.3.10 Engine I/O ...........................................................................................................................3-7
1.3.11 Panel I/O .............................................................................................................................3-7
1.3.12 Video I/O .............................................................................................................................3-8
1.3.13 Scanner control ...................................................................................................................3-8
1.3.14 Power supply....................................................................................................................... 3-9
1.4 Engine PCB ....................................................................................................................3-10
1.5 Pow er Supply.................................................................................................................. 3-11
1.5.1 Low-voltage power supply.................................................................................................3-11
1.5.2 High-voltage power supply ................................................................................................3-12
2. M ECHANICS ........................................................................................................ 3-13
2.1 Overview of Printing Mechanism ....................................................................................3-13
2.2 Sc anner Mechanism.......................................................................................................3-14
2.3 Paper Transfer ...............................................................................................................3-15
2.3.1 Paper supply .....................................................................................................................3-15
2.3.2 Paper registration..............................................................................................................3-15
2.3.3 Paper eject ........................................................................................................................3-16
2.3.4 Duplex printing ..................................................................................................................3-16
2.4 Sens ors .......................................................................................................................... 3-17
2.4.1 Cov er sensors ...................................................................................................................3-17
2.4.2 T oner sensors ...................................................................................................................3-17
2.4.3 Cassette sensor / Paper empty sensor .............................................................................3-18
2.4.4 Paper eject sensor ............................................................................................................3-18
2.4.5 M P-PE sensor ...................................................................................................................3-19
2.4.6 Document cover sensor ....................................................................................................3-19
2.4.7 Document front sensor / Document rear sensor ...............................................................3-20
2.4.8 DX-sensor PCB ASSY.......................................................................................................3-20
fineline6

TABLE OF CONTENTS
i
2.4.9 Rear cover sensor.............................................................................................................3-21
2.4.10 HP sensor .........................................................................................................................3-21
2.5 Drum Unit .......................................................................................................................3-22
2.5.1 Photosensitiv e drum..........................................................................................................3-22
2.5.2 Primary charger.................................................................................................................3-22
2.5.3 T ransfer roller....................................................................................................................3-22
2.5.4 C leaner..............................................................................................................................3-22
2.6 T oner Cartridge .............................................................................................................. 3-22
2.7 Print Process ..................................................................................................................3-22
2.7.1 Charging ............................................................................................................................3-22
2.7.2 Ex posure stage .................................................................................................................3-23
2.7.3 Dev eloping ........................................................................................................................ 3-24
2.7.4 T ransfer.............................................................................................................................3-24
2.7.5 Fix ing stage....................................................................................................................... 3-25
CHAPTER 4 DISASSEMBLY AND RE-ASSEMBLY ..............................4-1
1. S AFETY PRECAUTIONS ....................................................................................... 4-1
2. D ISASSEMBLY FLOW ........................................................................................... 4-2
3. DISASSEM BLY PROCEDURE ............................................................................... 4-3
3.1 AC Cord............................................................................................................................4-3
3.2 Drum Unit .........................................................................................................................4-3
3.3 Paper Tray........................................................................................................................4-4
3.4 DX Feed ASSY (MFC-8840D/8840DN, DCP-8045D/8045DN only) .............................. 4-14
3.5 Access Cover / Battery...................................................................................................4-17
3.6 Driver PCB Access Cover ..............................................................................................4-18
3.7 ADF Unit ......................................................................................................................... 4-19
3.8 Doc ument Scanner.........................................................................................................4-28
3.9 Panel Unit .......................................................................................................................4-33
3.10 Rear Cover C (MFC-8440, DCP-8040 only)...................................................................4-36
3.11 Outer Chute (MFC-8440, DCP-8040 only) ..................................................................... 4-37
3.12 Rear Cover MP ASSY / Outer Chute MP ASSY
(MFC-8840D/8840DN, DCP-8045D/8045DN only) ........................................................4-38
3.13 Rear Cover L/R............................................................................................................... 4-39
3.14 Side Cover L/R ...............................................................................................................4-40
3.15 J oint Cover ..................................................................................................................... 4-41
3.16 Front Cover ASSY (MFC-8440, DCP-8040 only) ........................................................... 4-45
3.17 MP Unit (MFC-8840D/8840DN, DCP-8045D/8045DN only) .......................................... 4-46
3.18 Rear Cover Sensor.........................................................................................................4-51
3.19 NCU (MFC-8440/8840D/8840DN only) .......................................................................... 4-52
3.20 Fix ing Unit....................................................................................................................... 4-53
3.21 Las er Unit .......................................................................................................................4-62
3.22 Main PCB .......................................................................................................................4-64
3.23 Base Plate / LV Insulation Sheet .................................................................................... 4-66
3.24 DX-Sensor PCB ASSY (MFC-8840D/8840DN, DCP-8045D/8045DN only)................... 4-67
3.25 Engine PCB ....................................................................................................................4-68
3.26 High-voltage PS PCB ASSY........................................................................................... 4-69
3.27 Low-voltage PS PCB ASSY............................................................................................ 4-70
fineline6

MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
3.28 Paper Feeder.................................................................................................................. 4-71
3.29 Frame L / Drive Unit ....................................................................................................... 7-78
3.30 Reversing Release Solenoid (MFC-8840D/8840DN, DCP-8045D/8045DN only).......... 4-82
3.31 T hermistor ASSY............................................................................................................ 4-83
3.32 Fan Motor 60 Unit LV / Fan Motor 60 Unit...................................................................... 4-83
3.33 Fram e R..........................................................................................................................4-84
4. P ACKING.............................................................................................................. 4-86
5. GUIDELINES FOR LEAD FREE SOLDER............................................................ 4-87
6. SCREW TORQUE LIST........................................................................................ 4-90
7. L UBRICATION...................................................................................................... 4-92
8. H ARNESS ROUTING ........................................................................................... 4-97
CHAPTER 5 PERIODIC MAINTENANCE ...............................................5-1
1. C ONSUMABLE PARTS .......................................................................................... 5-1
1.1 Drum Unit .........................................................................................................................5-1
1.2 T oner Cartridge ................................................................................................................ 5-3
2. PERIODICAL REPLACEMENT PARTS.................................................................. 5-7
2.1 Fixing Unit ......................................................................................................................... 5-8
2.2 Paper Feeding Kit ........................................................................................................... 5-16
3. P ERIODICAL CLEANING ..................................................................................... 5-20
3.1 Cleaning the Machine Exterior ....................................................................................... 5-20
3.2 Cleaning the Scanner ..................................................................................................... 5-20
3.3 Cleaning the Printer ........................................................................................................5-21
3.4 Cleaning the Drum Unit ..................................................................................................5-22
3.5 Cleaning the Scanner Window ....................................................................................... 5-22
3.6 Cleaning the Electrical Terminals ................................................................................... 5-23
4. MTBF / MTTR ....................................................................................................... 5-24
CHAPTER 6 TROUBLESHOOTING .......................................................6-1
1. INT RODUCTION .................................................................................................... 6-1
1.1 Initial Check ...................................................................................................................... 6-1
1.2 Warnings for Maintenance Work......................................................................................6-2
1.3 Identify the Problem.......................................................................................................... 6-3
2. ER ROR MESSAGE ................................................................................................ 6-4
2.1 Error Message on the LCD...............................................................................................6-4
2.2 Error Codes Shown in the “MACHINE ERROR X X” message........................................6-7
3. PAPER PROBLEMS ............................................................................................. 6-11
3.1 Paper Loading Problems ................................................................................................ 6-11
3.2 O riginal Jams..................................................................................................................6-12
3.2.1 Original is jammed in the top of the ADF unit....................................................................6-12
3.2.2 Original is jammed inside the ADF unit .............................................................................6-12
3.3 Paper Jams .................................................................................................................... 6-13
3.3.1 Clearing jammed paper.....................................................................................................6-13
3.3.2 Paper is jammed in the Duplex Tray (For MFC-8840D/8840DN, DCP-8045D/8045DN) ..6-16
3.3.3 Causes & countermeasures..............................................................................................6-17
fineline6

TABLE OF CONTENTS
i
3.4 Paper Feeding Problems................................................................................................ 6-18
4. SOFTWARE SETTING PROBLEMS .................................................................... 6-20
5. M ALFUNCTIONS.................................................................................................. 6-23
6. TROUBLESHOOTING OF THE CONTROL PANEL ............................................. 6-28
7. TROUBLESHOOTING OF FAX FUNCTIONS ...................................................... 6-30
8. IM AGE DEFECTS................................................................................................. 6-34
8.1 Image Defect Examples ................................................................................................. 6-34
8.2 Diameter of Rollers......................................................................................................... 6-34
8.3 Troubleshooting Image Defect ....................................................................................... 6-35
8.4 Location of Grounding Contacts ..................................................................................... 6-53
8.4.1 Drum unit...........................................................................................................................6-53
8.4.2 Machine body & Paper tray ..............................................................................................6-53
9. IN CORRECT PRINTOUT ..................................................................................... 6-54
10. N ETWORK PROBLEM ......................................................................................... 6-56
10.1 Ins tallation Problem ........................................................................................................ 6-56
10.2 Interm ittent Problem ....................................................................................................... 6-57
10.3 T CP/IP Troubleshooting ................................................................................................. 6-58
10.4 UNIX Troubleshooting ....................................................................................................6-58
10.5 W indows® NT/LAN Server (TCP/IP) Troubleshooting.................................................... 6-59
10.6 W indows® 95/98/Me Peer to Peer Print (LPR) Troubleshooting ....................................6-59
10.7 W indows® 95/98/Me Peer to Peer (HP JetAdmin Compatible Method) Troubleshooting ........6-59
10.8 W indows® 95/98/Me/NT 4.0/2000 Peer to Peer Print (NetBIOS) Troubleshooting ........6-60
10.9 Brother Internet Print (TCP/IP) Troubleshooting ............................................................ 6-60
10.10 Windows® 95/98/Me/2000/XP IPP Troubleshooting....................................................... 6-60
10.11 Novell Netware Troubleshooting .................................................................................... 6-61
10.12 AppleTalk Troubleshooting .............................................................................................6-62
10.13 DLC/LLC Troubleshooting .............................................................................................. 6-62
10.14 Web Browser Troubleshooting (TCP/IP)........................................................................ 6-62
10.15 Internet Fax Troubleshooting.......................................................................................... 6-63
CHAPTER 7 MAINTENANCE MODE......................................................7-1
1. ENTRY INTO THE MAINTENANCE MODE............................................................ 7-1
2. LIST OF MAINTENANCE–MODE FUNCTIONS ..................................................... 7-2
3. DETAILED DESCRIPTION OF MAINTENANCE-MODE FUNCTIONS ................... 7-4
3.1 EEPROM Parameter Initialization (Maintenance mode 01/91) ........................................ 7-4
3.2 Printout of Scanning Compensation Data (Maintenance mode 05) ................................. 7-5
3.3 Placement of CCD Unit in Position for Transportation (Maintenance mode 06) .............. 7-7
3.4 ADF Performance Test (Maintenance mode 08) ............................................................. 7-7
3.5 Test Pattern 1 (Maintenance mode 09)............................................................................ 7-8
3.6 Firmware Switch Setting and Printout ..............................................................................7-9
3.6.1 Firmware switch setting (Maintenance mode 10)................................................................7-9
3.6.2 Printout of firmware switch data (Maintenance mode 11) .................................................7-11
3.7 Operation Check of LCD (Maintenance mode 12) ......................................................... 7-12
3.8 Operational Check of Control Panel PCB (Maintenance mode 13) ...............................7-13
3.9 Sensor Operational Check (Maintenance mode 32) ......................................................7-14
3.10 Received Data Transfer Function (Maintenance mode 53)............................................7-16
fineline6

MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
vii
3.11 Fine Adjustment of Scan Start/End Positions (Maintenance mode 54).......................... 7-18
3.12 CCD Scanner Area Setting (Maintenance mode 55) ..................................................... 7-20
3.13 EEPROM Customizing (Maintenance mode 74) ............................................................ 7-21
3.14 Printing out of Machine Log Information (Maintenance mode 77).................................. 7-22
3.15 Display of the Equipment’s Log Information (Maintenance mode 80)............................7-24
3.16 Machine Error Code Indication (Maintenance mode 82) ................................................ 7-26
3.17 Output of Transmission Log to the Telephone Line (Maintenance mode 87) ................7-26
3.18 Cancellation of the Memory Security Mode (Not applicable to the Japanese version) .7-27
APPENDIX 1 EEPROM CUSTOMIZING CODES ...................................A-1
APPENDIX 2 INSTALLING THE UPDATE DATA....................................A-3
1. INSTALLING THE UPDATE DATA TO THE MACHINE.......................................... A-3
1.1 Connecting the Machine to Your PC ................................................................................A-3
1.2 Setting up the Machine and Your PC ...............................................................................A-3
1.3 Installing the Update Data onto the Flash ROM of the Machine ......................................A-4
2. SETTING ID CODES TO MACHINES..................................................................... A-5
2.1 Connecting the Machine to Your PC ................................................................................A-5
2.2 Setting Up the Machine and Your PC...............................................................................A-5
2.3 Running the Setup Utility ..................................................................................................A-6
APPENDIX 3 FIRMWARE SWITCHS (WSW) .........................................A-7
APPENDIX 4 CIRCUIT DIAGRAMS
4.1 Main PCB Circuit Diagram (1/7) .....................................................................................A-50
4.2 Main PCB Circuit Diagram (2/7) .....................................................................................A-51
4.3 Main PCB Circuit Diagram (3/7) .....................................................................................A-52
4.4 Main PCB Circuit Diagram (4/7) .....................................................................................A-53
4.5 Main PCB Circuit Diagram (5/7) .....................................................................................A-54
4.6 Main PCB Circuit Diagram (6/7) .....................................................................................A-55
4.7 Main PCB Circuit Diagram (7/7) .....................................................................................A-56
4.8 Driver PCB Circuit Diagram ...........................................................................................A-57
4.9 Engine PCB Circuit Diagram (1/2)..................................................................................A-58
4.10 Engine PCB Circuit Diagram (2/2)..................................................................................A-59
4.11 NCU PCB Circuit Diagram (U.S.A.)................................................................................A-60
4.12 NCU PCB Circuit Diagram (Europe) ..............................................................................A-61
4.13 NCU PCB Circuit Diagram (Asia) ...................................................................................A-62
4.14 NCU PCB Circuit Diagram (Oceania).............................................................................A-63
4.15 Control Panel PCB Circuit Diagram................................................................................A-64
4.16 Low-voltage Power Supply PCB Circuit Diagram (200V) ...............................................A-65
4.17 Low-voltage Power Supply PCB Circuit Diagram (100V) ...............................................A-66
4.18 High-voltage Power Supply PCB Circuit Diagram (200V) ..............................................A-67
4.19 High-voltage Power Supply PCB Circuit Diagram (100V) ..............................................A-68
fineline6

MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
4- 1
CHAPTER 4 DISASSEMBLY AND RE-ASSEMBLY
1. SAFETY PRECAUTIONS
To avoid creating secondary problems by mishandling, follow the warnings and precautions below
during maintenance work.
WARNING
(1) Always turn off the power switch and unplug the power cord from the power outlet
before accessing any parts inside the printer.
(2) Some parts inside the printer are extremely hot immediately after the printer is
used. When opening the front cover or rear cover to access any parts inside the
printer, never touch the red colored parts shown in the following figures.
!
CAUTION:
(1) Be careful not to lose screws, washers, or other parts removed.
(2) Be sure to apply grease to the gears and applicable positions specified in this chapter.
(3) When using soldering irons or other heat-generating tools, take care not to accidentally
damage parts such as wires, PCBs and covers.
(4) Before handling any PCBs, touch a metal portion of the equipment to discharge any static
electricity charge on your body, or the electronic parts or components may be damaged.
(5) When transporting PCBs, be sure to wrap them in the correct protective packaging.
(6) Be sure to replace self-tapping screws correctly, if removed. Unless otherwise specified,
tighten screws to the following torque values.
TAPTITE, BIND or CUP B
M3: 0.7N  m
M4: 0.8N  m
TAPTITE, CUP S
M3: 0.8N  m
SCREW
M3: 0.7N  m
M4: 0.8N  m
(7) When connecting or disconnecting cable connectors, hold the connector body, not the
cables. If the connector has a lock, release the connector lock first to release it.
(8) After a repair, check not only the repaired portion but also all connectors. Also check that
other related portions are functioning properly before operational checks.
fineline6

440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
6-1
CHAPTER 6 TROUBLESHOOTING
1. INTRODUCTION
1.1 Initial Check
(1) O perating environment
Chec k if:
• The source voltage stays within ±10% from the rated voltage shown on the rating plate.
• The machine is installed on a solid, level surface.
• The room temperature is maintained between 10°C and 32.5°C. The relative humidity
is maintained between 20% and 80%.
• The machine is not located in a dusty place.
• The machine is not exposed to ammonia fumes or other harmful gases.
• The machine is not located in a hot or humid area (such as near water or a humidifier).
• The machine is not exposed to direct sunlight.
• The room is well-ventilated.
• The machine is not placed where the ventilation hole of the machine is blocked.
(2) Pr int paper
Check if :
• A recommended type of print paper is being used. [If the paper is too thick or too thin,
or tends to curl, paper jams or paper feed problems may occur, or printed images may
be blurred.]
• The print paper is damp. [If so, use fresh paper, and check whether the print quality
improves or not.]
• The print paper is short-grained paper or acid paper. [If so, print quality problems may
occur.]
For further information on paper, refer to subsection 2.12 ‘Paper’ in CHAPTER 1.
(3) Cons umable parts
Chec k if:
• The LCDs on the machine control panel indicate “Toner Empty”. If the LCDs indicate
“Toner Empty”, replace the cartridge with a new one.
For further information on consumable parts, refer to 1. ‘CONSUMABLE PARTS’ in
CHAPTER 5.
fineline6

CHAPTER 6 TROUBLESHOOTING
6-2
(4) Oth ers
Condensation:
When the machine is moved from a cold room into a warm room in cold weather,
condensation may occur inside the machine, causing various problems as listed below:
• Condensation on the optical surfaces such as the scanning mirror, lenses, the reflection
mirror and the protection glass may cause the print image to be light.
• If the photosensitive drum is cold, the electrical resistance of the photosensitive layer is
increased, making it impossible to obtain the correct contrast when printing.
• Condensation on the corona unit may cause corona charge leakage.
• Condensation on the hopper plate and separation pad may cause paper feed troubles.
If condensation has occurred, print several pages or leave the machine for 2 hours to allow it to
reach room temperature.
If the drum unit is unpacked soon after it is moved from a cold room to a warm room,
condensation may occur inside the unit, which may cause incorrect images. Instruct the user
to allow the unit to come to room temperature before unpacking it. This will take one or two
hours.
1.2 Warnings for Maintenance Work
To avoid creating secondary problems by mishandling, follow the warnings below during
maintenance work.
WARNING
(1)Always turn off the power switch and unplug the power cord from the power outlet
before accessing any parts inside the machine.
(2) Some parts inside the machine are extremely hot immediately after the machine is
used. When opening the front cover or rear cover to access any parts inside the
machine, never touch the shaded parts shown in the following figures.
fineline6

Brother DCP-8040 8045D 8045DN MFC-8440 8840D 8840DN service manual
Brother DCP-8040 8045D 8045DN MFC-8440 8840D 8840DN service manual
Brother DCP-8040 8045D 8045DN MFC-8440 8840D 8840DN service manual
Brother DCP-8040 8045D 8045DN MFC-8440 8840D 8840DN service manual
Brother DCP-8040 8045D 8045DN MFC-8440 8840D 8840DN service manual
Brother DCP-8040 8045D 8045DN MFC-8440 8840D 8840DN service manual
Brother DCP-8040 8045D 8045DN MFC-8440 8840D 8840DN service manual
Brother DCP-8040 8045D 8045DN MFC-8440 8840D 8840DN service manual
Brother DCP-8040 8045D 8045DN MFC-8440 8840D 8840DN service manual