Brother Facsimile Equipment MFC7420 User Manual

Confidential FACSIMILE EQUIPMENT SERVICE MANUAL MODELS: MFC7420/7820N DCP7010/7020/7025

viii Confidential APPENDIX 6 CIRCUIT DIAGRAMS NCU PCB: MFC7420 (U.S.A. and CANADA models) NCU PCB: MFC7820N (U.S.A. and CANADA models) NCU PCB: MFC7

Confidential 5-29(9) Remove the diffusion film. (10) Release the two hooks “A” to remove the LCD. Diffusion film Panel cover BossesHooksHoo

Confidential 5-305.1.12 NCU PCB (1) Remove the two bind B M4x12 taptite screws and one pan (S/P washer) M3.5x6 screw from the NCU unit. (2) Rem

Confidential 5-31(3) Remove the NCU harness ASSY. (4) Remove the two cup S M3x6 taptite screws from the NCU shield cover to remove the NCU PCB A

Confidential 5-32(2) Release the three hooks to remove the speaker cover. (3) Release the one hook to remove the speaker hold spring. Spe

Confidential 5-33(4) Remove the speaker ASSY. 5.1.14 Joint Cover ASSY /Paper Stopper/Battery ASSY (1) Remove the bind B M4x12 taptite sc

Confidential 5-34(2) Remove the two bind B M4x12 taptite screws and the rear chute cover spring. (3) Remove the inner chute. NOTE: Re-assemb

Confidential 5-35(4) Remove the battery ASSY and disconnect the connector. CAUTION: • There is a danger of explosion if the battery is incorrect

Confidential 5-36 5.1.15 Front Cover (1) Release the hook of the drive release cam from the front cover ASSY. (2) Release the hook “A” on the f

Confidential 5-37(4) Remove the paper stopper L. (5) Remove the paper stopper S from the paper stopper L. Paper stopper L Front cover Paper

Confidential 5-385.1.16 Pickup Roller Holder ASSY (1) Turn the printer upside down. (2) Remove the six bind B M4x12 taptite screws, and then remo

Confidential ixSAFETY PRECAUTIONS To use the MFC safely Please keep these instructions for later reference and read them before attempting any maint

Confidential 5-39<How to check> Take the Drum/Toner Unit out from the printer. Check that the distance between the floor and the separation

Confidential 5-40(3) Remove the spring extension P/R from the gear 52 P/R. (4) Release the hook and remove the gear 52 P/R. (5) Remove the bus

Confidential 5-41(7) Remove the link lever from the hook of the pickup roller holder ASSY. (8) Remove the pickup roller holder ASSY. NOTE: The

Confidential 5-425.1.17 Fixing Unit (1) Disconnect the heater harness connector and thermistor harness connector. (2) Remove the two cup B M4x12

Confidential 5-43(5) Remove the two PR arm ASSY and two PR bush from the pressure roller. (6) Release each hook of the springs from the fuser f

Confidential 5-44(7) Remove the two pan (S/P washer) M3x8 screws. (8) Remove the heat roller. (9) Remove the halogen heater. Screw, pan (S/P

Confidential 5-45NOTE: When re-assembling the heat roller, assemble the HR bush onto the fuser frame referring to the figure below. NOTE: When

Confidential 5-46(10) Remove the HR gear. (11) Remove the two HR bush. (12) Remove the thermistor ASSY harness from the four hooks. (13) Remov

Confidential 5-47NOTE: When re-assembling the thermistor ASSY to the fuser frame, ensure the direction of the thermistor ASSY is correct referring

Confidential 5-485.1.18 High-Voltage PS PCB ASSY (1) Disconnect the three connectors from the high-voltage PS PCB ASSY. (2) Disconnect the high-

Confidential x WARNING • When you move the MFC, grasp the side hand holds that are under the scanner. DO NOT carry the MFC by holding it at the b

Confidential 5-495.1.19 Main PCB < DCP7010/7020/7025, MFC7420 > (1) Disconnect the thirteen connectors from the main PCB. (2) Remove th

Confidential 5-50< MFC7820N > (1) Disconnect the thirteen connectors from the main PCB. (2) Remove the five cup S M3x6 taptite screws an

Confidential 5-515.1.20 PS PCB Unit (1) Remove the duct film. (2) Remove the pan (S/P washer) M3.5 x 6 screw and FG harness ASSY 1. (3) Remove

Confidential 5-52(8) Remove the pan (S/P washer) M3.5x6 screw, and then remove the ground wire. (9) Remove the bind B M4x12, taptite screw, and t

Confidential 5-53(11) Remove the two cup S M3x6 taptite screws. (12) Disconnect the three connectors from the PS PCB unit, and then remove the PS

Confidential 5-545.1.21 Laser Unit (1) Remove the cup S M3x6, taptite screw (A) and FG harness ASSY 6. (2) Remove the four cup S M3x6, taptite s

Confidential 5-55(4) Remove the filter ASSY from the air duct. (5) Remove the two cup S M3x6, taptite screws, and then remove the air duct. NOT

Confidential 5-565.1.22 Sub Chute ASSY (1) Remove the two bind B M4x12, taptite screws, and then remove the sub chute ASSY. Chute Taptite, bi

Confidential 5-575.1.23 Link Lever (1) Turn the printer body upside down. (2) Pull the “A” section outwards and remove the link lever. NOTE: W

Confidential 5-585.1.24 Tail Edge Actuator (1) Remove the tail edge actuator with the tail edge spring. (2) Remove the tail edge spring from the

Confidential xiCHOOSING A LOCATION Place your MFC on a flat, stable surface that is free of vibration and shocks, such as a desk. Put the MFC near

Confidential 5-595.1.26 Regist Sensor PCB ASSY (1) Remove the bind B M3x6, taptite screw. (2) Release the harness from the hook and remove the re

Confidential 5-605.1.28 Fan Motor 60 Unit (1) Remove the three bind B M4x12, taptite screws and three FG harness ASSY 1, 4, 5. (2) Remove the bas

Confidential 5-615.1.29 Toner LED PCB ASSY/LED Holder (1) Remove the toner LED PCB ASSY from the main frame R. (2) Remove the LED holder from t

Confidential 5-625.1.30 New Toner Actuator/New Toner Actuator Spring (1) Remove the new toner actuator spring. (2) Release the hook and remove th

Confidential 5-635.1.32 Cover Sensor (1) Release the two hooks and remove the cover sensor from the main frame L. 5.1.33 Toner Sensor PCB ASSY

Confidential 5-645.1.34 Main Motor ASSY (1) Remove the HVPS insulation sheet. (2) Remove the five bind B M4x12, taptite screws, and then remove t

Confidential 5-655.1.35 Develop Joint (1) Remove the develop joint from the gear plate calking ASSY. 5.1.36 P/R Solenoid ASSY (1) Remove the b

Confidential 5-665.1.37 F/R Solenoid ASSY (1) Remove the gear ASSY from the main frame L. NOTE: The gear ASSY contains the small gears. Be care

Confidential 5-67(2) Remove the bind B M3x10, taptite screw. (3) Remove the F/R solenoid ASSY, the F/R solenoid lever and the solenoid release sp

Confidential 5-685.1.38 Main Frame L (1) Remove the two bind B M4x12, taptite screws, and then remove the main frame L. Main frame L Chu

Confidential CHAPTER 1PARTS NAMES & FUNCTIONS

Confidential 5-695.1.39 Main Frame R (1) Remove the three bind B M4x12, taptite screws, and then remove the main frame R. ChuteMain frame

Confidential 5-705.1.40 Harness Routing Laser unit1FG harness ASSY 1 / FG harness ASSY 52Laser unitLD harness 5PPolygon motor connectorFG harness

Confidential 5-71 Laser unitFG harness ASSY 63Regist sensor PCB ASSY4FG harness ASSY 6HoleHoleHookRibRibHookMain PCBChuteRegist sensor PCB ASSYPS P

Confidential 5-72 Fan motor 60 unitFan motor 60 unitToner LED PCB ASSYPS PCB unitHoleHoleHoleHoleHooksMain PCBHookHookHooksPrinter top side(Printer

Confidential 5-73 Toner sensor PCB ASSY7P/R solenoid ASSY / F/R solenoid ASSY8HookHookHookHigh-voltage PS PCB ASSYHigh-voltage PS PCB ASSYF/R solen

Confidential 5-74 New toner sensor / Cover sensor / Battery harness910Panel unitCover sensorNew toner sensorHolesHoleHookHookPanel PCBPanel unitDoc

Confidential 5-75 ADF unit11Document scanner12HooksHoleHoleHoleHoleHoleHoleADF motorADF sensor PCBADF unitDocumentscannerDocument scannerADF FG har

Confidential 5-76 NCU FG harnessNCU PCB13NCU PCBHoleMain PCBNCU FG harness14NCU unitHoleLV shield unitNCU FG harnessJoint cover ASSY

Confidential 5-77 15Speaker ASSYHookHookHookRibsRibRibSpeaker ASSYFrontMain PCBMain PCBJoint cover ASSYJoint cover ASSY

Confidential 5-78 5.2 LUBRICATION MU4MU4 * BG4: KANTO KASEI BG- MU (4 mm dia. Ball) PG2 * PG2: PG- 661 (2 mm dia. Ball) DEV drive gear Gear

Confidential CHAPTER 1 PARTS NAMES & FUNCTIONS This chapter contains external views and names of components and describes their functions. Inf

Confidential CHAPTER 6ADJUSTMENTS AND UPDATING OF SETTINGS, REQUIRED AFTER PARTS REPLACEMENT

Confidential CHAPTER 6 ADJUSTMENTS AND UPDATING OF SETTINGS, REQUIRED AFTER PARTS REPLACEMENT This chapter details adjustments and updating of sett

6-1 Confidential 6.1 IF YOU REPLACE THE MAIN PCB [ 1 ] Load update programs/data If the main PCB is replaced with a new one, write the update progr

6-2 Confidential 6.2 IF YOU REPLACE THE LASER SCANNER UNIT ASSY [ 1 ] Inputting the adjusted value of the laser scanner (1) Double-click the br

Confidential CHAPTER 7CLEANING

Confidential CHAPTER 7 CLEANING For the cleaning procedures of the drum unit and toner cartridge, refer to the User's Guide.

Confidential CHAPTER8MAINTENANCE MODE

Confidential CHAPTER 8 MAINTENANCE MODE This chapter describes the maintenance mode which is exclusively designed for the purpose of checks, setti

8-1 Confidential 8.1 ENTRY INTO THE MAINTENANCE MODE MFC7420/7820N Press the Menu/Set and Start keys. Next press the key four times to make the

8-2 Confidential 8.2 LIST OF MAINTENANCE-MODE FUNCTIONS Maintenance-mode Functions Function Code Function Reference Section (Page)01 EEPROM Paramet

1-1 Confidential 1.1 EQUIPMENT OUTLINE Front view Rear view ADF Document Output Support Flap Document Cover Power Switch Front Cover Paper

8-3 Confidential 8.3 USER-ACCESS TO THE MAINTENANCE MODE Basically, the maintenance-mode functions listed on the previous page should be accessed by

8-4 Confidential DCP7010/7020/7025 (1) Press the Menu, Start, Menu, and keys in this order. The "MAINTENANCE **" appears on the LCD. (2)

8-5 Confidential 8.4 DETAILED DESCRIPTION OF MAINTENANCE-MODE FUNCTIONS 8.4.1 EEPROM Parameter Initialization (Function code 01/91)  Function The

8-6 Confidential 8.4.2 Printout of Scanning Compensation Data (Function code 05)  Function The machine prints out the white and black level data fo

8-7 Confidential Scanning Compensation Data List a) b) c) d) e) f) g) h) i) j) k) l) m) n) q)

8-8 Confidential 8.4.3 Placement of CIS Unit in Position for Transportation (Function code 06)  Function This function is to move the CIS unit in p

8-9 Confidential 8.4.4 ADF Performance Test (Function code 08)  Function The machine counts the documents fed by the automatic document feeder (ADF

8-10 Confidential 8.4.5 Test Pattern 1 (Function code 09)  Function This function, much like the copying function, prints out test pattern 1 to all

8-11 Confidential 8.4.6 Firmware Switch Setting and Printout 8.4.6.1 Firmware switch setting (Function code 10)  Function The machine incorporates

8-12 Confidential Firmware Switches (WSW01 through WSW51) Continued WSW No. Function WSW38 V.34 transmission settings WSW39 V.34 transmission spee

1-2 Confidential 1.2 CONTROL PANEL MFC-7420 and MFC-7820N have similar control keys. 1. One-Touch Keys 6. Dial Pad Keys These 4 keys give you in

8-13 Confidential DCP7010/7020/7025 (1) Press the key or key several times to display the “MAINTENANCE 10” code on the LCD. Then press the Set ke

8-14 Confidential 8.4.6.2 Printout of firmware switch data (Function code 11)  Function The machine prints out the setting items and contents speci

8-15 Confidential Configuration List

8-14 Confidential 8.4.6.2 Printout of firmware switch data (Function code 11)  Function The machine prints out the setting items and contents speci

8-17 Confidential 8.4.8 Operational Check of Control Panel PCB (Function code 13)  Function This function allows you to check the control panel PCB

8-18 Confidential 8.4.9 Sensor Operational Check (Function code 32)  Function This function allows you to check whether the 9 sensors.  Operating

8-19 Confidential (2) Change the detecting conditions to check that the indication on the LCD changes according to the sensor states. For instance,

8-20 Confidential 8.4.10 Received Data Transfer Function (Function code 53) (Not applicable to DCP7010/7020/7025)  Function This function transfe

8-21 Confidential Cover page sample End page sample

8-22 Confidential 8.4.11 Fine Adjustment of Scan Start/End Positions (Function code 54) (Not applicable to DCP7010/

1-3 Confidential 5. Navigation Keys 11. Copy Keys (Temporary settings) Enlarge/Reduce Lets you reduce or enlarge copies depending upon the ratio yo

8-23 Confidential MAINTENANCEACCEPTED1. ADF 2. FBSCAN START ADJ.+-+-+-MAINTENANCEMAINTENANCE 5 and 4 select2 second later 1 or 2 select Menu/Set

8-24 Confidential 8.4.12 Acquisition of White Level Data and CIS Scanner Area Setting (Function code 55)  Function This function allows the machine

8-25 Confidential 8.4.14 EEPROM Customizing (Function code 74)  Function This function allows you to customize the EEPROM according to language, fu

8-26 Confidential 8.4.15 Display of the Equipment’s Log Information (Function code 80)  Function The equipment may display its log information on t

8-27 Confidential USB: USB Serial No. DRUM: Drum counter COVERAGE: Average black coverage TTL_PG: Total number of pages printed COPY: Number of

8-28 Confidential 8.4.16 Machine Error Code Indication (Function code 82)  Function This function displays an error code of the last error on the L

8-29 Confidential 8.4.18 Cancellation of the Memory Security Mode (Not applicable to DCP7010/7020/7025 and the Japanese model)  Function (Not appli

Confidential CHAPTER 9ERROR INDICATION AND TROUBLESHOOTING

Confidential CHAPTER 9 ERROR INDICATION AND TROUBLESHOOTING This chapter details error messages and codes that the incorporated self-diagnostic func

Confidential 9-19.1 ERROR INDICATION To help the user or the service personnel promptly locate the cause of a problem (if any), the facsimile equip

1-4 Confidential 1.3 COMPONENTS The equipment consists of the following major components: Scanner Unit Panel Unit Speaker ASSY Joint Cover ASSYLase

Confidential 9-2 ERROR MESSAGE CAUSE ACTION Print data is left in the MFC’s memory. Re-start printing from your computer. Data Remaining Print da

Confidential 9-3 ERROR MESSAGE CAUSE ACTION Machine too Hot The inside of the machine is too hot. Make sure that the fan in the MFC is spinning

Confidential 9-4 ERROR MESSAGE CAUSE ACTION Scanner Locked The scanner glass’s sensor does ot move to the home position. (For MFC-7420) Check wh

Confidential 9-5[ 2 ] Error codes shown in the "MACHINE ERROR X X" message Error Code (Hex) Symptom Probable Cause Solution 56 The back

Confidential 9-6 The solution when Error Code 76,77,78 shown in the machine: It’s pos

Confidential 9-7 The paper ejection roller does not rot

Confidential 9-8Error Code (Hex) Symptom Probable Cause Solution 89 Not used. 8A The paper feed motor does not rotate. (Not used.) 8B The

Confidential 9-9 Error Code (Hex) Symptom Probable Cause Solution AD-AE Not used. CIS flat cable broken ornot connected Correct the cable conne

Confidential 9-10 Error Code (Hex) Symptom Probable Cause Solution BC Not used. CIS defective Replace the scanner cover (scanner unit). BD Bla

Confidential 9-119.1.2 Communications Errors If a communications error occurs, the facsimile equipment (1) emits an audible alarm (intermittent beep

Confidential © Copyright Brother 2004 All rights reserved. No part of this publication may be reproduced in any form or by

Confidential CHAPTER 2SPECIFICATIONS

Confidential 9-12(3) Compatibility [checking the NSF and DIS] Code 1 Code 2 Causes 32 01 Remote terminal only with V.29 capability in 2400 or 4

Confidential 9-13(5) Command reception [checking the NSF and DIS after transmission of NSS and DCS] Code 1 Code 2 Causes 50 01 Vertical resolut

Confidential 9-14(10) Video signal reception Code 1 Code 2 Causes A0 03 Error correction sequence not terminated even at the final transmissio

Confidential 9-159.2 TROUBLESHOOTING 9.2.1 Introduction This section gives the service personnel some of the troubleshooting procedures to be follow

Confidential 9-169.2.4 Troubleshooting Based on Problem Type [ 1 ] Paper feeding problems Even if the paper is printed and ejected without any pr

Confidential 9-17 F-3 Page skew User Check (1) Check that the paper or other media is loaded into the paper tray correctly and that the paper guid

Confidential 9-18[ 2 ] Software setting problems The printer may not print the data correctly if there are incorrect software settings. S-1 “There

Confidential 9-19 S-2 Although the USB driver is installed, it is unable to find the BRUSB: port. (Windows98/Me only) User Check (1) Re-install th

Confidential 9-20 S-3 This printer does not appear in Chooser (Mac OS ® 9.1 to 9.2) or Print center (Mac OS ® X 10.2.4 or greater). User Check (1)

Confidential 9-21[ 3 ] Malfunction When taking countermeasures for malfunctions as described in this section, check connectors for contact failure

Confidential CHAPTER 2 SPECIFICATIONS This chapter lists the specifications of each model, which enables you to make a comparison of different mod

Confidential 9-22WARNING: If you analyze malfunctions with the power plug inserted into the power outlet, special caution should be exercised even

Confidential 9-23 M-5 Insufficient output from high-voltage power supply unit Possible cause Step Check ResultRemedy High-voltage contact 1 Do any

Confidential 9-24 M-8 Fixing unit failure Possible cause Step Check ResultRemedy Poor thermistor harness contact 1 Is the contact of connector CN

Confidential 9-25 M-10 Pickup function of paper tray does not work. Possible cause Step Check ResultRemedy Link lever does not move smoothly. 1 Do

Confidential 9-26 M-12 Maximum speed is slow. Possible cause Step Check ResultRemedy Two or more sheets of the paper in the tray are pulled to fee

Confidential 9-27 [ 4 ] Image defects 1-1 Light 1-2 Dark 1-3 Completely blank 1-4 All black 1-5 Dirt on the back of paper 1-6 Black

Confidential 9-28 I-1 Light User Check (1) Check the printer’s environment. Conditions such as humidity, high temperatures, etc. may cause this

Confidential 9-29 I-2 Dark User Check (1) Check the paper used meets the recommended paper specifications. (2) Check the printer’s environment.

Confidential 9-30 I-3 Completely blank Possible cause Step Check ResultRemedy Ground contacts Developing bias contact failure 1 Are the develo

Confidential 9-31 I-4 All black User Check (1) Clean the corona wire of the drum unit. (2) The drum unit may be damaged. Install a new drum unit

2-1 Confidential 2.1 GENERAL 2.1.1 General Specifications Memory Capacity 16 MB (MFC-7420), 32 MB (MFC-7820N) Automatic Document Feeder (ADF) U

Confidential 9-32 I-5 Dirt on the back of paper Possible cause Step Check ResultRemedy Fixing unit dirty 1 Is the pressure roller dirty? Is any o

Confidential 9-33 I-6 Black and blurred vertical streaks User Check (1) Clean the corona wire in the drum unit. (2) Check that the wire cleaner

Confidential 9-34 I-7 Black and blurred horizontal stripes User Check (1) The drum unit may be damaged. Install a new drum unit. (2) Check the

Confidential 9-35 I-9 White vertical streaks User Check (1) Try to wipe the scanner window with a soft cloth. (2) The toner cartridge may be da

Confidential 9-36 I-11 Faulty registration Possible cause Step Check Result Remedy Excessive paper load 1 Is the paper loaded in the paper tray

Confidential 9-37 I-12 Poor fixing Possible cause StepCheck ResultRemedy Print paper 1 Is thick paper of more than 43lb being used? Yes Reco

Confidential 9-38 I-13 Image distortion Possible cause StepCheck ResultRemedy Laser unit installation 1 Is the laser unit secured to the frame

Confidential 9-39 I-15 White spots User Check (1) If the problem is not solved after printing a few pages, the drum unit may have glue from label

Confidential 9-40NOTE: Clean the drum unit as follows. (1) Remove the toner cartridge from the drum unit. Place the printing samples in front of t

Confidential 9-41 I-16 Black spots User Check (1) If the problem is not solved after printing a few pages, the drum unit may have glue from label

2-2 Confidential 2.1.2 Paper Specifications (1) Paper type Paper type Tray1 Manual feed slot Select the paper type from the printer driver Plain pap

Confidential 9-42 I-17 Black band Possible cause StepCheck ResultRemedy Ground contacts Corona failure 1 Is the wire cleaner at its home posit

Confidential 9-43 I-18 Gray background Possible cause StepCheck ResultRemedy No Recommend to use the specified types of paper. Print paper 1 D

Confidential 9-44 I-19 Hollow print User Check (1) Check the paper used meets the recommended paper specifications. (2) Select the ‘Thick paper mo

Confidential 9-45 I-21 Horizontal lines Possible cause StepCheck ResultRemedy Paper tray contacts 1 Are the ground contacts on the right side o

Confidential 9-46 I-23 Ghost User Check (1) Check the paper used meets the recommended paper specifications. Damp paper, thick media or rough su

Confidential 9-47 Location of Grounding Contacts • Drum unit • Printer body & paper tray (2) Wire cleaner Toner cartridge (4) Devel

Confidential 9-48[ 5 ] Incorrect printout When the data is not printed correctly as it is seen on the PC screen, follow the procedures below in the

Confidential 9-49 P-3 Unable to print full pages of a document with the “MEMORY FULL” message. User Check (1) Press the Start key on the control

Confidential 9-50[ 6 ] Network problem If the error related to network occurs, refer to the following sections;  Installation problem The Bro

Confidential 9-51(5) Make the following selection. Make sure that your print server appears. If it is visible, then the connection is good. Otherw

2-3 Confidential (4) Recommended paper Europe USA Plain paper Xerox Premier 80 g/m2 Xerox Business 80 g/m2 Modo Paper DATACOPY 80 g/m2 IGEPA X-pr

Confidential 9-52For Macintosh® For Mac OS® 9.1 to 9.2 (1) From the Apple menu, open the Chooser. (2) Click the Brother Laser (IP) icon, and make su

Confidential 9-53<Windows® 95/98/Me and Windows NT® 4.0 Peer-to-Peer print (NetBIOS) troubleshooting> If you are having trouble printing on a

Confidential 9-54[ 7 ] Troubleshooting of the control panel L-1 Nothing is displayed on the LCD. User Check (1) Verify if the power switch is turn

Confidential 9-55 L-2 The control panel does not work. User Check (1) No Possible cause Step Check Result Remedy Key sticking 1 Any key on co

Confidential 9-56[ 8 ] Troubleshooting of fax functions F-1 FAX can't send it. User Check (1) Verify that the telephone cord is securely inse

Confidential 9-57 F-2 Speed dialing and One-touch dialing can't be used. Possible cause Step Check ResultRemedy Speed dialing, One-touch diali

Confidential 9-58 F-3 FAX can't be received. User Check (1) Verify that the telephone cord is securely inserted. Possible cause Step Check Re

Confidential 9-59 F-5 Speaker is silent during on-hook dialing. Possible cause Step Check Result Remedy Connection between main PCB and speaker 1

Confidential MFC7420/7820N DCP7010/7020/7025 APPENDIX 1. SERIAL NUMBERING SYSTEM This appendix shows the location of serial number labels put o

App. 1-1 Confidential SERIAL NUMBERING SYSTEM Individual machines have a serial number label for the machine itself and a property label for the he

2-4 Confidential 2.1.3 Printable Area When using PCL emulation, the edges of the paper that cannot be printed on are shown below. PortraitABCDEFGFGE

App. 1-2 Confidential (2) Laser unit serial label REGARDING X delay and Y delay It indicates required delay amount for writing in each of main

Confidential MFC7420/7820N DCP7010/7020/7025 APPENDIX 2. FIRMWARE INSTALLATION This appendix provides instructions on how to update firmware st

App. 2-1 Confidential A2.1 INSTALLING THE UPDATE DATA TO THE MACHINE If you want to update the current program stored in the flash ROM of the main P

App. 2-2 Confidential Installing the Update Data onto the Flash ROM of the Machine  On a PC running Windows 95 (1) Copy the update data and transfe

App. 2-3 Confidential  If you use USB cable Preparation You need to have the BHL2-Maintenance Printer driver and FILEDG32.exe (provided by Brother

App. 2-4 Confidential (6) The following screen appears, indicating the detection of new hardware device by the system. Click Next to proceed. (7)

App. 2-5 Confidential (9) Select the folder where the copy of the BHL2-Maintenance Printer driver is located (or click Browse to specify it), then c

App. 2-6 Confidential (12) If the driver is successfully installed, the following message window appears. Click Finish to return to Windows. NOTE:

App. 2-7 Confidential Writing the update programs/data onto the flash ROM of the machine After the installation procedure of the printer driver, proc

App. 2-8 Confidential (3) MFC7420/7820N Press the * and # keys at the same time when the machine is on standby. The firmware version appears on the

2-5 Confidential The table below shows the printable areas when printing on Portrait for each paper size. Size A B C D E F G Letter 215.9 mm 8

App. 2-9 Confidential A2.2 SETTING ID CODES TO MACHINES Brother driver machines are assigned unique ID codes (character strings) at the factory. If

Confidential MFC7420/7820N DCP7010/7020/7025 APPENDIX 3. CUSTOMIZING CODES ACCORDING TO SHIPPING DESTINATION This appendix lists the customizin

App. 3-1 Confidential EEPROM CUSTOMIZING CODES This function allows you to customize the EEPROM according to language, function settings, and firmw

Confidential MFC7420/7820N DCP7010/7020/7025 APPENDIX 4. FIRMWARE SWITCHES (WSW) This appendix describes the functions of the firmware switches

App. 4-1 Confidential WSW No. Function Refer to: WSW01 Dial pulse setting App. 4-3 WSW02 Tone signal setting App. 4-4 WSW03 PABX mode setting

App. 4-2 Confidential WSW No. Function Refer to: WSW38 V.34 transmission settings App. 4-42 WSW39 V.34 transmission speed App. 4-43 WSW40 V.3

App. 4-3 Confidential WSW01 (Dial pulse setting) Selector No. Function Setting and Specifications 1 2 Dial pulse generation mode No. 1 2 0 0 : N

App. 4-4 Confidential  Selector 7: Switching between pulse (DP) and tone (PB) dialing, by the function switch This selector determines whether or

App. 4-5 Confidential WSW03 (PABX* mode setting) Selector No. Function Setting and Specifications 1 CNG detection when sharing a modular wall socket

App. 4-6 Confidential  Selectors 6 and 7: Dial tone detection in PABX (Not used.) These selectors activate or deactivate the dial tone detection f

2-6 Confidential Landscape ABCDEFGFGEGGPhysical pagePrintable areaLogical pageB Physical page lengthD Maximum logical page

App. 4-7 Confidential  Selector 4: Dual tone detection sensitivity in ICM recording Setting this selector to "1" increases the tone dete

App. 4-8 Confidential  Selectors 1 through 3: 1st dial tone detection These selectors activate or deactivate the 1st dial tone detection functi

App. 4-9 Confidential WSW06 (Redial/Pause key setting and 2nd dial tone detection) Selector No. Function Setting and Specifications 1 | 3 Redial/P

App. 4-10 Confidential  Selectors 1 through 3: Redial/Pause key setting and 2nd dial tone detection Selectors 1 2 3 0 0 0 No WAIT is inser

App. 4-11 Confidential WSW07 (Dial tone setting 1) Selector No. Function Setting and Specifications 1 2 Dial tone frequency band control No. 1 2

App. 4-12 Confidential WSW08 (Dial tone setting 2) Selector No. Function Setting and Specifications 1 | 3 1st dial tone detection time length No. 1

App. 4-13 Confidential WSW09 (Protocol definition 1) Selector No. Function Setting and Specifications 1 Frame length selection 0: 256 octets 1:

App. 4-14 Confidential WSW10 (Protocol definition 2) Selector No. Function Setting and Specifications 1 Not used. 2 Time length from transmission

App. 4-15 Confidential WSW11 (Busy tone setting) Selector No. Function Setting and Specifications 1 2 Busy tone frequency band control No. 1 2 0

App. 4-16 Confidential WSW12 (Signal detection condition setting) Selector No. Function Setting and Specifications 1 2 Min. detection period requir

2-7 Confidential The table below shows the printable areas when printing on Landscape for each paper size. Size A B C D E F G Letter 279.4 mm

App. 4-17 Confidential WSW13 (Modem setting) Selector No. Function Setting and Specifications 1 2 Cable equalizer No. 1 2 0 0 : 0 km 0 1 : 1

App. 4-18 Confidential WSW14 (AUTO ANS facility setting) Selector No. Function Setting and Specifications 1 2 Frequency band selection (lower limit

App. 4-19 Confidential WSW15 (REDIAL facility setting) Selector No. Function Setting and Specifications 1 2 Redial interval No. 1 2 0 0 : 5 min

App. 4-20 Confidential WSW16 (Function setting 1) Selector No. Function Setting and Specifications 1 Not used. 2 ITU-T (CCITT) superfine recommenda

App. 4-21 Confidential WSW17 (Function setting 2) Selector No. Function Setting and Specifications 1 2 Off-hook alarm No. 1 2 0 0 : No alarm 0 1

App. 4-22 Confidential WSW18 (Function setting 3) Selector No. Function Setting and Specifications 1 Not used. 2 3 Detection enabled time for CNG

App. 4-23 Confidential WSW19 (Transmission speed setting) Selector No. Function Setting and Specifications 1 | 3 First transmission speed choice for

App. 4-24 Confidential WSW20 (Overseas communications mode setting) Selector No. Function Setting and Specifications 1 EP* tone prefix 0: OFF

App. 4-25 Confidential  Selectors 8: Limitation on CNG detection If this selector is set to "1," the machine detects a CNG signal accord

App. 4-26 Confidential WSW22 (ECM and call waiting caller ID) Selector No. Function Setting and Specifications 1 ECM* in sending 0: ON 1:

2-8 Confidential 2.2 SPECIFICATIONS LIST MFC7420/7820N (1/15) US/Canada Europe Asia/Pacific US/Canada Europe Asia/PacificModel NameGENERAL Print Eng

App. 4-27 Confidential WSW23 (Communications setting) Selector No. Function Setting and Specifications 1 Starting point of training check (TCF) 0: F

App. 4-28 Confidential WSW24 (TAD setting 2) Selector No. Function Setting and Specifications 1 2 Maximum OGM recording time No. 1 2 0 0 : 15 sec.

App. 4-29 Confidential WSW25 (TAD setting 3) Selector No. Function Setting and Specifications 1 | 4 Not used. 5 | 7 Pause between paging number and

App. 4-30 Confidential WSW26 (Function setting 4) Selector No. Function Setting and Specifications 1 2 Not used. 3 Dialing during document reading

App. 4-31 Confidential WSW27 (Function setting 5) Selector No. Function Setting and Specifications 1 Not used. 2 Ringer OFF setting 0: Yes 1

App. 4-32 Confidential WSW28 (Function setting 6) Selector No. Function Setting and Specifications 1 | 3 Transmission level of DTMF high-band frequen

App. 4-33 Confidential WSW29 (Function setting 7) Selector No. Function Setting and Specifications 1 | 3 Compression threshold level for voice signal

App. 4-34 Confidential WSW30 (Function setting 8) Selector No. Function Setting and Specifications 1 | 3 Dial tone/busy tone detection level during r

App. 4-35 Confidential WSW31 (Function setting 9) Selector No. Function Setting and Specifications 1 Not used. 2 Default reduction rate for failure

App. 4-36 Confidential WSW32 (Function setting 10) Selector No. Function Setting and Specifications 1 | 4 Not used. 5 6 Default resolution No. 5 6

i Confidential PREFACE This Service Manual is intended for use by service personnel and details the specifications, construction, theory of operatio

2-9 Confidential (2/15) US/Canada Europe Asia/Pacific US/Canada Europe Asia/PacificModel NameGENERAL Power Source120V AC50/60(Canada)Hz120V AC50/60(

App. 4-37 Confidential WSW33 (Function setting 11) Selector No. Function Setting and Specifications 1 | 3 Detection threshold level of "no tone&

App. 4-38 Confidential WSW34 (Function setting 12) Selector No. Function Setting and Specifications 1 | 3 Erasing time length of ICM tone recorded pr

App. 4-39 Confidential WSW35 (Function setting 13) Selector No. Function Setting and Specifications 1 | 4 Max. detection period of dial tone/busy to

App. 4-40 Confidential WSW36 (Function setting 14) Selector No. Function Setting and Specifications 1 ECP mode* (Not used.) 0: ON 1: OFF 2 Recover

App. 4-41 Confidential  Selectors 6 through 8: Extension of incoming calling signal (CI) frequency band specified by selectors 1 through 4 on WSW1

App. 4-42 Confidential WSW38 (V.34 transmission settings) Selector No. Function Setting and Specifications 1 2 Setting of the equalizer No. 1 2 0

App. 4-43 Confidential WSW39 (V.34 transmission speed) Selector No. Function Setting and Specifications 1 | 4 First transmission speed choice for fa

App. 4-44 Confidential WSW40 (V.34 modem settings) Selector No. Function Setting and Specifications 1 2 Not used. 3 | 8 Masking of symbol rate(s)

App. 4-45 Confidential Symbol rate Transmission speed (bps) Symbol rate Transmission speed (bps) Symbol rate Transmission speed (bps) 2400 2400 30

App. 4-46 Confidential WSW41 (ON-duration of the scanning light source) Selector No. Function Setting and Specifications 1 | 3 ON-duration of the sca

2-10 Confidential (3/15) US/Canada Europe Asia/Pacific US/Canada Europe Asia/PacificModel NameTELEPHONETelephone Index (Search)Pre-registered for FA

App. 4-47 Confidential WSW42 (Internet mail settings) Selector No. Function Setting and Specifications 1 Access to the incoming mail (POP3) server (P

App. 4-48 Confidential WSW44 (Speeding up scanning-1) Selector No. Function Setting and Specifications 1 | 5 Not used. 6 | 8 Effective time length o

App. 4-49 Confidential WSW45 (Speeding up scanning-2) Selector No. Function Setting and Specifications 1 | 3 Delay time from when documents are set u

App. 4-50 Confidential WSW46 (Monitor of power ON/OFF state and parallel port kept at high) Selector No. Function Setting and Specifications 1 2 Mon

App. 4-51 Confidential WSW47 (Switching between high- and full-speed USB) Selector No. Function Setting and Specifications 1 Handling paper at the o

App. 4-52 Confidential WSW48 (USB setup latency) Selector No. Function Setting and Specifications 1 | 5 Not used. 6 | 8 USB setup latency No. 6 7

App. 4-53 Confidential WSW50 (SDAA settings) Selector No. Function Setting and Specifications 1 2 Percentage voltage for interpreting the external t

App. 4-54 Confidential WSW51 (Function setting 16) Selector No. Function Setting and Specifications 1 Output of communications error report when tran

Confidential MFC7420/7820N DCP7010/7020/7025 APPENDIX 5. WIRING DIAGRAM This appendix provides the wiring diagram that helps you understand the

LANParallelInterfaceCN501CN18CHRGCN500-12-7-10RDPS-5-4-3-2-1SLVCC5TELOFFCIVCC24PLSCMLS0VCN9-2-1VOUT2VOUT1J2LINEJ1EXTRL1-6RL2/POL-8FGR-GNDG-GNDB-GNDCLK

2-11 Confidential (4/15) US/Canada Europe Asia/Pacific US/Canada Europe Asia/PacificModel NameFAXMemory Transmission (ITU-T Chart)ECM (Error Correct

Confidential MFC7420/7820N DCP7010/7020/7025 APPENDIX 6. CIRCUIT DIAGRAMS This appendix provides the circuit diagrams of the NCU PCB and power

A. NCU PCB: MFC7420(U.S.A. and CANADA models)Confidential

A. NCU PCB: MFC7820N(U.S.A. and CANADA models)Confidential

A. NCU PCB:MFC7420(EUROPE models)Confidential

A. NCU PCB: MFC7820N(EUROPE models)Confidential

B. Power Supply PCB 100V(U.S.A. and CANADA models)Confidential

B. Power Supply PCB 200V(EUROPE models) Confidential

December '04 SM-FAX036(2) 8C5A03 Printed in Japan

2-12 Confidential (5/15) US/Canada Europe Asia/Pacific US/Canada Europe Asia/PacificModel NameINTERFACECable includedAcceptable Media Card SlotPRINT

2-13 Confidential (6/15) US/Canada Europe Asia/Pacific US/Canada Europe Asia/PacificModel NameCOPYResolution(dpi)Manual Duplex Copy N in 1PosterImag

2-14 Confidential (7/15) US/Canada Europe Asia/Pacific US/Canada Europe Asia/PacificModel NameBUNDLED SOFTWARE (ForWindows)WebBRAdmin (*5)Network

2-15 Confidential (8/15) US/Canada Europe Asia/Pacific US/Canada Europe Asia/PacificModel NameOptional NETWORK (*6)Model NameShare PrinterShare

2-16 Confidential DCP7010/7020/7025 (9/15) US/Canada Europe Asia/PacificModel NameDCP-7020GENERAL Print EngineCPU Speed

2-17 Confidential (10/15) US/Canada Europe Asia/PacificModel NameDCP-7020GENERAL Power Source120V AC50/60(Canada)HzPower Consumption (Copying)Power

2-18 Confidential (11/15) US/Canada Europe Asia/PacificModel NameDCP-7020TELEPHONETelephone Index (Search)Pre-registered for FAX BACKSYSTEM ( USA )C

ii Confidential CHAPTER 8 MAINTENANCE MODE Describes the maintenance mode which is exclusively designed for the purpose of checks, settings and adj

2-19 Confidential (12/15) US/Canada Europe Asia/PacificModel NameDCP-7020FAXPolling Receiving Auto ReductionDuplex Fax ReceiveOut-of-Paper Reception

2-20 Confidential (13/15) US/Canada Europe Asia/PacificModel NameDCP-7020PRINTERFonts Disk BasedPaper Handling Size LTR

2-21 Confidential (14/15) US/Canada Europe Asia/PacificModel NameDCP-7020MESSAGE CENTER/MESSAGEMANAGERTAD TypeICM Recording TimeOGM (MC;MC Pro;Pagin

2-22 Confidential (15/15) US/Canada Europe Asia/PacificModel NameDCP-7020PHOTO CAPTURE CENTER N/A N/AStandard NETWORKShare PrinterShare ScannerSh

Confidential CHAPTER 3THEORY OF OPERATION

Confidential CHAPTER 3 THEORY OF OPERATION This chapter gives an overview of the scanning and printing mechanisms as well as the sensors, actuator

Confidential 3-13.1 OVERVIEW Control SectionCentronicsparallel interfaceUSB interfaceHost ComputerControlpanelLANinterfacePrinterdataFax dataLow- an

Confidential 3-23.2 MECHANICAL COMPONENTS Pinch roller Drum/toner ASSYPaper feed rollerRegist front actuator Pinch roller Separation roller Tai

Confidential 3-33.2.1 Scanner Mechanism This mechanism consists of the document cover, the scanner unit (scanner cover), and the automatic document

Confidential 3-4 This scanner mechanism supports a dual scanning system: ADF scanning and flat-bed scanning. They automatically switch to the fo

iii Confidential TABLE OF CONTENTS CHAPTER 1 PARTS NAMES & FUNCTIONS 1.1 EQUIPMENT OUTLINE...

Confidential 3-5(1) ADF scanning: Document moves across stationary CIS unit Placing a document face up in the document support activates the docume

Confidential 3-63.2.2 Printing Mechanism 3.2.2.1 Paper supply The feed roller picks up a few sheets or one sheet of paper from the paper tray every

Confidential 3-7(1) The paper is gripped between the separation roller and separation pad and separated into individual sheets. The separation roll

Confidential 3-83.2.2.2 Push-up function of paper tray In order to improve the transfer function of the paper tray, the pressure plate in the paper

Confidential 3-9 Pickup roller holder ASSY Paper tray Up plate gearUp plateGear 17Pressure plate Sector cam Hook B Hook C Link leverHook A Hook C H

Confidential 3-103.2.2.3 Paper registration After the paper top position is detected by the regist front actuator, the paper, separated into indivi

Confidential 3-113.2.2.4 Paper eject After the printing image on the exposure drum is transferred onto the paper, the paper is fed to the fixing un

Confidential 3-123.2.2.6 Toner cartridge Develops the electrostatic latent image on the exposure drum with toner and forms the visible image.  To

Confidential 3-13 New toner detection mechanism The printer detects the amount of the remaining toner with the sensor and indicates the timing

Confidential 3-14When the new toner detection switch detects that the toner cartridge is replaced with a new one, the developing bias voltage is in

iv Confidential CHAPTER 5 DISASSEMBLY/REASSEMBLY AND LUBRICATION 5.1 DISASSEMBLY/REASSEMBLY ...

Confidential 3-153.2.2.7 Print process  Charging The drum is charged to approximately 900V by an ion charge which is generated by the primary c

Confidential 3-163. The laser beams reflected by the reflection mirror go straight toward the exposure drum below it, then expose the exposure drum

Confidential 3-17 Transfer (1) Transfer process After the drum has been charged and exposed, and has received a developed image, the toner form

Confidential 3-183.2.3 Sensors and Actuators Sensor name Sensor type Location Cover sensor Mechanical switch Main frame L Toner LED PCB (Light

Confidential CHAPTER 4 TRANSFER OF DATA LEFT IN THE MACHINE TO BE SENT FOR REPAIR

Confidential CHAPTER 4 TRANSFER OF DATA LEFT IN THE MACHINE TO BE SENT FOR REPAIR This chapter describes how to transfer data left in the machine

Confidential 4-14.1 TRANSFERRING RECEIVED FAX DATA When the machine at the user site requires to be repaired, unplugging the power cord from the wa

Confidential 4-2Cover page sample End page sample

Confidential CHAPTER 5DISASSEMBLY/REASSEMBLY AND LUBRICATION

v Confidential 5.1.24 Tail Edge Actuator...5-58 5.1.25 R

Confidential CHAPTER 5 DISASSEMBLY/REASSEMBLY AND LUBRICATION This chapter details procedures for disassembling and reassembling the machine togeth

Confidential 5.1.18 High-Voltage PS PCB ASSY...5-48 5.1.19 Main PCB ...

Confidential 5-1 5.1 DISASSEMBLY/REASSEMBLY  Safety Precautions To prevent the creation of secondary problems by mishandling, observe the follow

Confidential 5-2  Tightening Torque Location of screw Screw type Q'ty Tightening torque N•m (kgf•cm) Side cover L Taptite, bind B M4x1

Confidential 5-3  Preparation Prior to proceeding with the disassembly procedure, (1) Unplug - the modular jack of the telephone line, - the U

Confidential 5-4  Disassembly Flowchart 1234567814161818191921213132333132331934342020282829293915171516171091312112124252727232322302637353

Confidential 5-5 5.1.1 AC Cord (1) Disconnect AC cord from the machine. 5.1.2 Drum/Toner ASSY (1) Open the front cover and remove the drum/to

Confidential 5-6 5.1.3 Paper Tray (1) Close the front cover and pull out the paper tray. (2) Remove the paper from the paper tray. (3) Remove

Confidential 5-7 5.1.4 Rear Cover (1) Remove the rear cover. NOTE: Remove the “A” section of the rear cover while opening the rear cover slightly.

Confidential 5-8 5.1.5 Rear Chute Cover (1) Remove the rear chute cover. (2) Remove the paper eject actuator and the eject actuator spring.

vi Confidential CHAPTER 7 CLEANING CHAPTER 8 MAINTENANCE MODE 8.1 ENTRY INTO THE MAINTENANCE MODE ...

Confidential 5-9 5.1.6 Side Cover L (1) Open the front cover. (2) Remove the two bind B M4x12 taptite screws, and then remove the side cover L.

Confidential 5-105.1.7 Side Cover R (1) Remove the two bind B M4x12 taptite screws, and then remove the side cover R. Taptite, bind B M4x12 Ta

Confidential 5-115.1.8 ADF unit (1) Open the ADF unit and scanner unit. (2) Remove the one cup S M3x6 taptite screw and ADF FG harness and FB FG

Confidential 5-12(5) Close the ADF unit and scanner unit. (6) Remove the two pins and remove the ADF cover. (7) Release the two hooks from t

Confidential 5-13(9) Remove the two pressure rollers from the pressure roller shaft. (10) Open the ADF unit. (11) Release the hook to remove t

Confidential 5-14(12) Close the ADF unit. (13) Remove the separate roller shaft ASSY and bushing from the ADF unit. (14) Remove the four cup B

Confidential 5-15(16) Remove the separation rubber ASSY from the upper document chute. (17) Remove the separation rubber from the ADF plate

Confidential 5-16(18) Remove the two cup B M3x10 taptite screws from the lower document chute. (19) Release the two hooks to remove the lower doc

Confidential 5-17(21) Remove the two ejection rollers from the pressure roller shaft. (22) Remove the ADF unit ejection spring from the ADF

Confidential 5-18(23) Release the two hooks and remove the resin bearing. (24) Remove the LF roller ASSY from the lower document chute. (25) R

vii Confidential CHAPTER 9 ERROR INDICATION AND TROUBLESHOOTING 9.1 ERROR INDICATION ...

Confidential 5-19(27) Remove the two cup B M3x10 taptite screws and one cup S M3x6 taptite screw from the lower document chute. (28) Remove the

Confidential 5-20NOTE: When re-assembling drive frame ASSY, assemble it so that the arm ASSY is at the top. (31) Remove the document rear ac

Confidential 5-21(32) Remove the document front actuator from the lower document chute. (33) Release the two hooks “A” on the lower document c

Confidential 5-22(35) Turn the lower document chute upside down. (36) Remove the pins and remove the document hold. (37) Remove the document spr

Confidential 5-23(41) Remove the two springs. (42) Remove the pressure roller ASSY. (43) Remove the two pressure rollers from the pressure

Confidential 5-24(44) Remove the three cup B M3x10 taptite screws to remove the hinge ASSY L. (45) Remove the hinge from the hinge arm. (46) Rem

Confidential 5-255.1.9 Pull Arm/Pull Arm Guide/Lock Claw Pull Arm Spring (1) Open the scanner unit. (2) Release the hook to remove the scanner u

Confidential 5-265.1.10 Scanner Unit (1) Disconnect the flat cable from the main PCB. (2) Remove the scanner unit from the machine. 5.1.11 Pane

Confidential 5-27(3) Disconnect the connector from the panel PCB ASSY. (4) Release the three hooks to remove the panel unit from the scanner unit

Confidential 5-28(7) Remove the rubber key. NOTE: When re-assembling the rubber key, make sure that the key works correctly. (8) Release the t