Brother MFC8440D User manual

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
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.

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
© Copyright Brother Industries, Ltd. 2004
All rights reserved.
No part of this publication may be reproduced in any form or by any means without permission
in writing from the publisher.
Specifications are subject to change without notice.
Trademarks:
The brother logo is a registered trademark of Brother Industries, Ltd.
Apple, the Apple Logo, and Macintosh are trademarks, registered in the United States and
other countries, and TrueType is a trademark of Apple computer, Inc.
Microsoft and MS-DOS are registered trademarks of Microsoft Corporation.
Windows is a registered trademark of Microsoft Corporation in the U.S. and other countries.

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MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
i
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.

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TABLE OF CONTENTS
ii
TABLE OF CONTENTS
REGULATION............................................................................................ viii
SAFETY INFORMATION .............................................................................. x
CHAPTER 1 GENERAL........................................................................... 1-1
1. OVERVIEW ............................................................................................................ 1-1
2. SPECIFICATIONS.................................................................................................. 1-3
2.1 General.............................................................................................................................1-3
2.2 General (Continued).........................................................................................................1-3
2.3 Print Media .......................................................................................................................1-4
2.4 Copy .................................................................................................................................1-4
2.5 Fax....................................................................................................................................1-5
2.6 Scanner ............................................................................................................................1-6
2.7 Printer ...............................................................................................................................1-6
2.8 Interfaces..........................................................................................................................1-7
2.9 Consumable Items ...........................................................................................................1-7
2.10 Network (LAN) Board (NC-9100h) ...................................................................................1-7
2.11 Computer 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 Power Supply....................................................................................................................2-1
1.2 Environment .....................................................................................................................2-1
2. UNPACKING........................................................................................................... 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

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SERVICE MANUAL
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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. ELECTRONICS ...................................................................................................... 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 ROM....................................................................................................................................3-4
1.3.5 Flash ROM .......................................................................................................................... 3-5
1.3.6 SDRAM ...............................................................................................................................3-5
1.3.7 Optional RAM...................................................................................................................... 3-6
1.3.8 EEPROM.............................................................................................................................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 Power Supply..................................................................................................................3-11
1.5.1 Low-voltage power supply.................................................................................................3-11
1.5.2 High-voltage power supply ................................................................................................3-12
2. MECHANICS ........................................................................................................ 3-13
2.1 Overview of Printing Mechanism ....................................................................................3-13
2.2 Scanner 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 Sensors ..........................................................................................................................3-17
2.4.1 Cover sensors ...................................................................................................................3-17
2.4.2 Toner sensors ................................................................................................................... 3-17
2.4.3 Cassette sensor / Paper empty sensor ............................................................................. 3-18
2.4.4 Paper eject sensor ............................................................................................................3-18
2.4.5 MP-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

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TABLE OF CONTENTS
iv
2.4.9 Rear cover sensor ............................................................................................................. 3-21
2.4.10 HP sensor ......................................................................................................................... 3-21
2.5 Drum Unit .......................................................................................................................3-22
2.5.1 Photosensitive drum.......................................................................................................... 3-22
2.5.2 Primary charger................................................................................................................. 3-22
2.5.3 Transfer roller.................................................................................................................... 3-22
2.5.4 Cleaner..............................................................................................................................3-22
2.6 Toner Cartridge ..............................................................................................................3-22
2.7 Print Process ..................................................................................................................3-22
2.7.1 Charging............................................................................................................................3-22
2.7.2 Exposure stage .................................................................................................................3-23
2.7.3 Developing ........................................................................................................................3-24
2.7.4 Transfer.............................................................................................................................3-24
2.7.5 Fixing stage....................................................................................................................... 3-25
CHAPTER 4 DISASSEMBLY AND RE-ASSEMBLY .............................. 4-1
1. SAFETY PRECAUTIONS ....................................................................................... 4-1
2. DISASSEMBLY FLOW ........................................................................................... 4-2
3. DISASSEMBLY 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 Document 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 Joint 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 Fixing Unit.......................................................................................................................4-53
3.21 Laser 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

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SERVICE MANUAL
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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 Thermistor ASSY............................................................................................................4-83
3.32 Fan Motor 60 Unit LV / Fan Motor 60 Unit......................................................................4-83
3.33 Frame R..........................................................................................................................4-84
4. PACKING.............................................................................................................. 4-86
5. GUIDELINES FOR LEAD FREE SOLDER............................................................ 4-87
6. SCREW TORQUE LIST........................................................................................ 4-90
7. LUBRICATION...................................................................................................... 4-92
8. HARNESS ROUTING ........................................................................................... 4-97
CHAPTER 5 PERIODIC MAINTENANCE ............................................... 5-1
1. CONSUMABLE PARTS .......................................................................................... 5-1
1.1 Drum Unit .........................................................................................................................5-1
1.2 Toner Cartridge ................................................................................................................5-3
2. PERIODICAL REPLACEMENT PARTS .................................................................. 5-7
2.1 Fixing Unit .........................................................................................................................5-8
2.2 Paper Feeding Kit ...........................................................................................................5-16
3. PERIODICAL 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. INTRODUCTION .................................................................................................... 6-1
1.1 Initial Check ......................................................................................................................6-1
1.2 Warnings for Maintenance Work ......................................................................................6-2
1.3 Identify the Problem..........................................................................................................6-3
2. ERROR 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 Original 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

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TABLE OF CONTENTS
vi
3.4 Paper Feeding Problems................................................................................................6-18
4. SOFTWARE SETTING PROBLEMS .................................................................... 6-20
5. MALFUNCTIONS.................................................................................................. 6-23
6. TROUBLESHOOTING OF THE CONTROL PANEL ............................................. 6-28
7. TROUBLESHOOTING OF FAX FUNCTIONS ...................................................... 6-30
8. IMAGE 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. INCORRECT PRINTOUT ..................................................................................... 6-54
10. NETWORK PROBLEM......................................................................................... 6-56
10.1 Installation Problem ........................................................................................................6-56
10.2 Intermittent Problem .......................................................................................................6-57
10.3 TCP/IP Troubleshooting .................................................................................................6-58
10.4 UNIX Troubleshooting ....................................................................................................6-58
10.5 Windows®NT/LAN Server (TCP/IP) Troubleshooting....................................................6-59
10.6 Windows®95/98/Me Peer to Peer Print (LPR) Troubleshooting ....................................6-59
10.7 Windows®95/98/Me Peer to Peer (HP JetAdmin Compatible Method) Troubleshooting........ 6-59
10.8 Windows®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

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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

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REGULATION
viii
REGULATION
LASER SAFETY (110 - 120V MODEL ONLY)
This printer is certified as a Class I laser product under the US Department of Health and
Human Services (DHHS) Radiation Performance Standard according to the Radiation
Control for Health and Safety Act of 1968. This means that the printer does not produce
hazardous laser radiation.
Since radiation emitted inside the printer is completely confined within the protective
housing and external covers. the laser beam cannot escape form the machine during any
phase of user operation.
FDA REGULATIONS (110 - 120V MODEL ONLY)
The US Food and Drug Administration (FDA) has implemented regulations for laser
products manufactured on and after August 2, 1976. Compliance is mandatory for
products marketed in the United States. One of the following labels on the back of the
printer indicates compliance with the FDA regulations and must be attached to laser
products marketed in the United States.
The label for Japanese manufactured products
MANUFACTURED: K
BROTHER INDUSTRIES, LTD.
15-1, Naeshiro-cho, Mizuho-ku, Nagoya 467-8561,
Japan.
This product complies with FDA radiation performance
standards, 21 CFR Subchapter J.
The label for Chinese manufactured products
MANUFACTURED: C
BROTHER Corporation (Asia) Ltd.
Shenzen Buji Nan Ling Factory
Gold Garden Ind., Nan Ling Village, Buji, Rong Gang,
Shenzen, CHINA
This product complies with FDA radiation performance
standards, 21 CFR Subchapter J.
Caution
Use of controls, adjustments or performance of procedures other than those specified in
this manual may result in hazardous radiation exposure.

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MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
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IEC 825 (220-240V MODEL ONLY)
This printer is a Class I laser product as defined in IEC 825 specifications. The label
shown below is attached in countries where required.
CLASS 1LASERP RODUCT
APPAREIL Å LASER DE CLASSE 1
LASER KLASSE 1 PRODUKT

This printer has a laser diode which emits invisible laser radiation in the Laser Unit. The
Laser Unit should not be opened without disconnecting the two connectors connected with
the AC power supply and laser unit. Since the variable resistor in the laser unit is adjusted
in accordance with the standards, never touch it.
Caution
Use of controls, adjustments or performance of procedures other than those specified in
this manual may result in hazardous radiation exposure.
For Finland and Sweden
LUOKAN 1 LASERLAITE
KLASS 1 LASER APPARAT
Varoitus! Laitteen käyttäminen muulla kuin tässä käyttöohjeessa mainitulla tavalla saattaa
altistaa käyttäjän turvallisuusluokan 1 ylittävälle näkymättömälle lasersäteilylle.
Varning – Om apparaten används på annat sätt än i denna Bruksanvisning specificerats,
kan användaren utsättas för osynlig laserstrålning, som överskrider gränsen för laserklass
1.

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SAFETY INFORMATION
x
SAFETY INFORMATION
CAUTION FOR LASER PRODUCT (WARNHINWEIS FUR LASER DRUCKER)
CAUTION: When the machine during servicing is operated with the cover open, the
regulations of VBG 93 and the performance instructions for VBG 93 are
valid.
CAUTION: In case of any trouble with the laser unit, replace the laser unit itself. To
prevent direct exposure to the laser beam, do not try to open the enclosure
of the laser unit.
ACHTUNG: Im Falle von Störungen der Lasereinheit muß diese ersetzt werden. Das
Gehäuse der Lasereinheit darf nicht geöffnet werden, da sonst
Laserstrahlen austreten können.
<Location of the laser beam window>
ADDITIONAL INFORMATION
When servicing the optical system of the printer, be careful not to place a screwdriver or
other reflective object in the path of the laser beam. Be sure to take off any personal
accessories such as watches and rings before working on the printer. A reflected beam,
though invisible, can permanently damage the eyes.
Since the beam is invisible, the following caution label is attached on the laser unit.

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MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
xi
DEFINITIONS OF WARNINGS, CAUTIONS AND NOTES
The following conventions are used in this service manual:
WARNING

Indicates wa rning s t h a t must b e ob se rved t o p reven t p ossible pe rsonal injur y.
!CAUTION:

Indicates cautions that must be observed to service the printer properly or prevent damage
to the printer.
NOTE:
Indicates notes and useful tips to remember when servicing the printer.
**Listed below are the various kinds of “WARNING” messages included in this manual.
WARNING

Al wa ys tur n off th e p ower s wi tch a nd u np lug th e po wer co rd f rom t he p ower o utlet
before accessing any parts ins ide the print er.
WARNING

Som e parts inside the printer are extremely hot im mediately after the printer is used.
Wh en ope ning the f ro nt cover or ba ck co ve r t o a ccess a ny p arts inside t he print er,
never tou ch the sha de d pa rts sh own in t he f ol lo wi ng f ig u r es.
WARNING

If you a nalyze malfunc ti on s w i th the p ow e r plu g i ns erted in to the p ow e r o utlet,
sp ecial c au tion sho ul d b e e xe rc is ed even if t he power s w i tc h i s O FF b ecause it is a
si ngle pole s wi tc h .

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MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
1-1
CHAPTER 1 GENERAL
1. OVERVIEW
<Front View>
Fig. 1-1
<Back View>
Fig. 1-2
ADF document support extension
Document cover
Power switch
Front cover
Automatic document feeder (ADF)
Control panel
Face-down output
tray support flap
Front cover release button
Manual feed tray
(MFC-8440, DCP-8040)
Multi-purpose tray (MP tray)
(MFC-8840D/8840DN,
DCP-8045D/8045DN)
ADF cover
Telephone line jack
USB interface connector
Parallel interface connector
External telephone line jack
Paper adjustment lever
for duplex printing
(MFC-8840D/8840DN,
DCP-8045D/8045DN)
Duplex tray
(MFC-8840D/8840DN,
DCP-8045D/8045DN)
AC power connector
Face-up output tray
(Back output tray)
ADF document output support flap
Paper tray (Tray #1)

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CHAPTER 1 GENERAL
1-2
<Inside View (Document Cover Open)>
Fig. 1-3
White film
Scanner glass
Document guidelines
Glass strip
Scanner lock lever
Document cover

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MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
1-3
2. SPECIFICATIONS
2.1 General
Memory Capacity 32 MB
Optional Memory 1 DIMM slot; Memory expandable up to 160 MB
Automatic Document Up to 50 pages
Paper Tray 250 Sheets (20 lb)
Multi-Purpose Tray 50 Sheets (20 lb) (MFC-8840D/8840DN, DCP-8045D/8045DN
only)
Manual Feed Tray Single sheet (20 lb) (MFC-8440, DCP-8040 only)
Printer Type Laser
Print Method Electrophotography by semiconductor laser beam scanning
LCD
(Liquid Crystal
Display)
22 characters x 5 lines
Warm-up Max. 18 seconds at 73.4°F (23°C)
Power Source 120V AC 50/60Hz (U.S.A., CANADA Version only)
Power Consumption Average Operating (Copying): 450 W or less (25°C)
Peak: 1090 W or less
Sleep: with Network 16 W or less
with out Network 14 W or less
Standby: 85 W or less (25°C)
Dimensions 20.7 x 17.3 x 18.3 (in.)
532 x 444 x 469 (mm)
Weight Without Drum/Toner Unit:
MFC-8440, DCP-8040: 36.6 lb/16.6 kg
MFC-8840D/8840DN, DCP-8045D/8045DN: 39.9 lb/18.1 kg
Noise Operating: 53 dB A or less
Standby: 30 dB A or less
2.2 General (Continued)
Temperature Operating: 50 - 90.5°F (10 - 32.5°C)
Storage: 32 - 104°F (0 - 40°C)
Humidity Storage: 20 to 80% (without condensation)
Operating: 10 to 90% (without condensation)

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CHAPTER 1 GENERAL
1-4
2.3 Print Media
Paper Input <Paper Tray>
•Paper type:
Plain paper, recycled paper and transparencies, envelopes
(Manual Feed/Multi-purpose Tray)
•Paper size:
A4, Letter, Legal, B5 (ISO), B5 (JIS), Executive, A5, A6,
B6 (ISO)
Weight: 16 - 28 lb (60 - 105 g/m2) (Paper Tray)
For more details, see Paper specifications for each paper
tray on page 1-10.
•Maximum paper tray capacity:
Approx. 250 sheets of 20 lb (80 g/m2) plain paper
•Maximum multi-purpose tray capacity:
Approx. 50 sheets of 20 lb (80 g/m2) plain paper
(MFC-8840D/8840DN, DCP-8045D/8045DN only)
< Manual Feed Tray/Multi-Purpose Tray >
•Paper size:
Width: 20 lb 2.75 - 8.66" (69.8 - 220.0 mm)
Height: 4.60 - 16.00" (116.0 - 406.4 mm)
Weight: 16 - 43 lb (60 - 161 g/m2)
Paper Output Up to 150 sheets of plain paper (Face up print delivery to the
output paper support)
2.4 Copy
Color/Monochrome Monochrome
Copy Speed Up to 21 copies/minute (Letter paper)
Up to 20 copies/minute (A4 paper)
Multiple Copies Stacks or Sorts up to 99 pages
Enlarge/Reduce 25% to 400% (in increments of 1%)
Resolution 600 dpi

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MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
1-5
2.5 Fax
Compatibility ITU-T Group 3
Coding System MH/MR/MMR/JBIG
Modem Speed 33600 bps
Automatic Fallback
Original Size ADF Width: 5.8" to 8.5" (148 mm to 216 mm)
ADF Height: 5.8" to 14.0" (148 mm to 356 mm)
Scanner Width: Max. 8.48" (212 mm)
Scanner Height: Max. 14.0" (356 mm)
Scanning Width 8.2 inches (208 mm)
Printing Width 8.2 inches (208 mm)
Gray Scale 64 levels
Polling Types Standard, Sequential
Contrast Control Automatic/Light/Dark (manual setting)
Resolution •Horizontal 203 dot/inch (8 dot/mm)
•Vertical
•Standard 98 line/inch (3.85 line/mm)
•Fine, Photo 196 line/inch (7.7 line/mm)
•Superfine 392 line/inch (15.4 line/mm)
One-Touch Dial 40 (20 x 2)
Speed-Dial 300 stations
Automatic Redial One time
Auto Answer 0, 1, 2, 3 or 4 rings
Communication
Source
Public switched telephone network.
Memory Transmission Up to 600 pages (Brother #1 Chart)
Out of Paper
Reception
Up to 600 pages (Brother #1 Chart)

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CHAPTER 1 GENERAL
1-6
2.6 Scanner
Color/Monochrome Color/Monochrome
TWAIN Compliant Yes (Windows®95/98/98SE/Me/2000 Professional and Windows
NT®Workstation Version 4.0)
WIA Compliant Yes (Windows
®
XP)
Resolution Up to 9,600 x 9,600 dpi (interpolated)*
Up to 600 x 2,400 dpi (optical)
* Maximum 1200 x 1200 dpi scanning with Windows®XP
(resolution up to 9600 x 9600 dpi can be selected by using the
Brother scanner utility)
Document Size ADF Width: 5.8" to 8.5" (148 mm to 216 mm)
ADF Height: 5.8" to 14.0" (148 mm to 356 mm)
Scanner Glass Width: Max. 8.5" (216 mm)
Scanner Glass Height: Max. 14.0" (356 mm)
Scanning Width 8.35 inches (212 mm)
Gray Scale 256 levels
Scanning Speed Color: 1.80 msec/line (Up to 300 x 300 dpi)
: 3.60 msec/line (400 x 400 dpi or higher)
Monochrome: 0.84 msec/line (ADF)
: 1.01 msec/line (Scanner Glass)
NOTE:
•Scanning directly to a networked PC is available with Windows®98/98SE/Me/2000
Professional and XP.
•OS X scanning is supported in OS X 10.2.1 or greater.
2.7 Printer
Emulation PCL6 (Brother Printing System for Windows®emulation mode of
HP LaserJet) and BR-Script (PostScript®) Level 3
Printer Driver Windows®95/98/98SE/Me/2000 Professional/XP and Windows
NT®Workstation Version 4.0 driver supporting Brother Native
Compression mode and bi-directional capability
Apple®Macintosh®Quick Draw®Driver and PostScript (PPD) for
OS 8.6-9.2/OS X 10.1/10.2.1 or Greater
Resolution HQ1200 (Max. 2400 x 600 dots/inch)
Print Quality Normal printing mode
Economy printing mode (saves toner usage)
Print Speed Up to 21 pages/minute letter size
Up to 20 pages/minute A4 size
(when loading paper from paper tray)
Duplex Printing Up to 9 images/minute: (MFC-8840D/8840DN,
DCP-8045D/8045DN only)
First Print Up to 12 seconds (using letter size paper in paper tray)

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MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
1-7
2.8 Interfaces
Interface Recommended Cable
Parallel A bi-directional shielded parallel cable that is IEEE 1284 compliant
and not longer than 6 feet (2 m).
USB A Hi-Speed USB 2.0 cable that is not longer than 6 feet (2 m).
NOTE:
•Please make sure that you use a Hi-Speed USB 2.0 certified cable if your computer uses a
Hi-Speed USB 2.0 interface.
•Even if your computer has a USB 1.1 interface you can connect the MFC.
•To meet FCC/CISPR emission requirements for the MFC, you must attach the included
filter core and cable tie to the parallel interface cable.
2.9 Consumable Items
Toner Cartridge Life
Expectancy
TN-540/TN-3030: Standard Toner Cartridge - Up to 3,500* pages
TN-570/TN-3060: High Yield Toner Cartridge - Up to 6,700* pages
*(when printing letter size or A4 paper at 5% print coverage)
NOTE:
Toner life expectancy will vary depending upon the type of
average print job.
Drum Unit Life
Expectancy
Up to 20,000 pages/drum unit (DR-3000)
NOTE:
There are many factors that determine the actual drum life, such
as temperature, humidity, type of paper, toner you use and
number of pages per print job.
2.10 Network (LAN) Board (NC-9100h)
MFC-8440/8840D
(Option)
MFC-8840DN
(Standard)
DCP-8040/8045D
(Option)
When you add the optional Network (LAN) Board (NC-9100h), you
can connect your MFC into the network to use the Internet FAX,
Network Scanner, Network Printer and Network Management
software operations for small workgroups.
NOTE:
SMTP/POP3 E-mail Services are required for Internet Fax.
Support for:
Windows® 95/98/Me/NT
®
4.0/2000/XP Novell NetWare 3.X,
4.X, 5.X Mac OS 8.6 - 9.2, X 10.0-10.2.1 or Greater Ethernet
10/100 BASE-TX Auto Negotiation TCP/IP, IPX/SPX,
AppleTalk, DLC/LLC RARP, BOOTP, DHCP, APIPA,
NetBIOS, WINS LPR/LPD, Port9100, SMTP/POP3
SMB(NetBIOS/ IP), IPP, SSDP, Rendezvous, FTP MIBII as
well as Brother private MIB TELNET, SNMP, HTTP, TFTP
Included Utilities:
BRAdmin Professional and Web Based
Management
NOTE:
•Scanning directly to a networked PC is not supported in
Windows ® 95, NT
®
and Mac OS.
•BRAdmin Professional is not supported in Mac OS.