Brother DP-525CJ User manual

R
WORD PROCESSOR
SERVICE MANUAL
MODEL:DP-525CJ/DP-530CJ/DP-540CJ/DP-550CJ
LW-800ic/LW-810ic/LW-810icBL/LW-840ic
REVISED EDITION

SERVICE MANUAL
i
CONTENTS
PART I THEORY OF OPERATION
CHAPTER 1 MECHANICAL THEORY....................................................................... 1-1
1. Ink Jet Printer...........................................................................................................1-1
1.1. Ink Jet Printer System Configuration .......................................................................... 1-2
1.2. Ink Jet Operation........................................................................................................ 1-4
1.2.1. Paper Feed Mechanism................................................................................ 1-4
1.2.2. Carriage Assembly ....................................................................................... 1-7
1.2.3. Carriage Motion Control.............................................................................. 1-10
1.2.4. Maintenance Station Operation................................................................... 1-11
1.2.4.1. Spitting................................................................................................. 1-12
1.2.4.2. Wiping.................................................................................................. 1-13
1.2.4.3. Capping................................................................................................ 1-14
1.2.4.4. Purging................................................................................................. 1-14
1.2.5. Sensors...................................................................................................... 1-15
1.2.5.1. Carriage Home Position Sensor............................................................ 1-15
1.2.5.2. PE Sensor ............................................................................................ 1-16
1.3. INK CHG (Ink Change) Functions............................................................................. 1-17
1.3.1. Ink Cartridge Installation/Replacement ....................................................... 1-17
1.3.2. Automatic Print head Cleaning (Purging).................................................... 1-17
2. Keyboard................................................................................................................1-18
CHAPTER 2 ELECTRICAL THEORY........................................................................ 2-1
1. System Configuration...............................................................................................2-1
1.1. Main PCB (Printed Circuit Board)............................................................................... 2-1
1.2. Switch PCB (Printed Circuit Board)............................................................................. 2-1
1.3. Keyboard FPC (Flexible Printed Circuit)..................................................................... 2-1
1.4. FDD (Floppy Disk Drive) Module................................................................................ 2-1
1.5. CRT Display............................................................................................................... 2-1
2. Ink Jet Printer Configuration..................................................................................... 2-3
2.1. Ink Cartridge............................................................................................................... 2-3
2.2. Carriage Motor ........................................................................................................... 2-3
2.3. Line Feed Motor......................................................................................................... 2-3
2.4. Carriage Home Position Sensor.................................................................................. 2-3
2.5. PE (Paper End) Sensor .............................................................................................. 2-3

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3. Power Supply Circuit................................................................................................ 2-4
3.1. Configuration.............................................................................................................. 2-4
3.2. +24V Generator.......................................................................................................... 2-5
3.3. +5V Generator............................................................................................................ 2-5
4. Reset Circuit.............................................................................................................2-6
4.1. Configuration.............................................................................................................. 2-6
5. CBIC and Peripherals...............................................................................................2-7
5.1. CBIC #9 ..................................................................................................................... 2-7
5.2. Main ROM (#12, #13)................................................................................................. 2-7
5.3. Main RAM (#10, #11) ................................................................................................. 2-7
5.4. Video RAM (#7).......................................................................................................... 2-7
5.5. Printer Driver Circuits (#2, #3, Q1 to Q4, and Q14 to Q17)......................................... 2-7
5.6. FDC (Floppy Disk Controller)...................................................................................... 2-7
5.7. Clock Circuit............................................................................................................... 2-8
5.8. Buzzer Drive Circuit ................................................................................................... 2-8
5.9. Country Specification Change-over ............................................................................ 2-9
5.10. RS-232C I/F Circuit.................................................................................................. 2-10
6. Printer Control........................................................................................................2-11
6.1. Ink Jet Head Control................................................................................................. 2-11
6.2. Carriage Motor Control............................................................................................. 2-12
6.3. Line Feed Motor Control........................................................................................... 2-13
6.4. Carriage Home Position Sensor................................................................................ 2-14
6.5. PE Sensor................................................................................................................ 2-14
7. Switch PCB ............................................................................................................ 2-15
7.1. Configuration............................................................................................................ 2-15
8. Keyboard System...................................................................................................2-16
8.1. FPC Operation ......................................................................................................... 2-16
8.2. Keyboard Scan......................................................................................................... 2-17
8.3. Keyboard Control Circuit........................................................................................... 2-18
9. CRT Control ........................................................................................................... 2-20
9.1. Configuration............................................................................................................ 2-20
9.2. SRAM and Display Screen Relationship................................................................... 2-21
9.2.1. SRAM (#7) Access ..................................................................................... 2-22
9.2.2. CRT Display Timing Chart.......................................................................... 2-23
10. FDD (Floppy Disk Drive) Control ............................................................................2-24
10.1. FDD Configuration.................................................................................................... 2-24
10.2. FDD Operation......................................................................................................... 2-25
10.2.1. Basic Operation.......................................................................................... 2-25
10.2.2. Interface between CBIC (#8) and FDC (#5)................................................. 2-25
10.3. FDD Module............................................................................................................. 2-26

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10.3.1. Read/Write Circuit...................................................................................... 2-26
10.3.2. Motor Drive Circuit...................................................................................... 2-26
10.3.3. Sensor Circuits........................................................................................... 2-26
PART II REPAIR
CHAPTER 3 TROUBLESHOOTING.......................................................................... 3-1
1. Introduction ..............................................................................................................3-1
2. Precautions.............................................................................................................. 3-1
2.1. Personal Safety.......................................................................................................... 3-1
2.2. Handling ESD-Sensitive Parts.................................................................................... 3-1
3. Checks Before Repair..............................................................................................3-2
4. Checks After Repair.................................................................................................3-3
5. Troubleshooting Flow Charts....................................................................................3-4
6. Failure Analysis........................................................................................................3-6
7. SELF-TESTS..........................................................................................................3-13
7.1. SERIAL NUMBER Input Display............................................................................... 3-13
7.2. Self Print Mode......................................................................................................... 3-14
7.3. Self-Test Mode......................................................................................................... 3-17
7.3.1. Display (CRT) Test..................................................................................... 3-19
7.3.1.1. Cross Hatch Pattern Test...................................................................... 3-20
7.3.1.2. Full Dot Screen Test............................................................................. 3-21
7.3.1.3. Blank Screen Test ................................................................................ 3-22
7.3.1.4. H Pattern Test ...................................................................................... 3-23
7.3.1.5. mw Pattern Test.................................................................................... 3-24
7.3.1.6. Dot Pattern Test.................................................................................... 3-25
7.3.2. Print Checks............................................................................................... 3-26
7.3.2.1. Print Test Pattern 1............................................................................... 3-26
7.3.2.2. Print Test Pattern 2............................................................................... 3-29
7.3.2.3. Dot Patterns.......................................................................................... 3-31
7.3.3. Keyboard Tests........................................................................................... 3-33
7.3.4. FDD Tests.................................................................................................. 3-36
7.3.4.1. FDD Test.............................................................................................. 3-36
7.3.4.2. Special FDD Test.................................................................................. 3-37
7.3.4.3. FDD SW Test....................................................................................... 3-41
7.3.4.4. FDD Write Error Rate Check ................................................................ 3-42
7.3.4.5. FDD Read Error Rate Check................................................................. 3-44
7.3.5. PE (Paper-End) Sensor Test....................................................................... 3-46
7.3.6. CR (Carriage Reset) Test ........................................................................... 3-47

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7.3.7. DISK TYPE ................................................................................................ 3-48
7.3.8. RS-232C Test ("Echo Back") ...................................................................... 3-49
CHAPTER 4 COMPONENT DISASSEMBLY............................................................. 4-1
1. Covers...................................................................................................................... 4-1
1.1. Upper Cover............................................................................................................... 4-2
1.1.1. Removing the Upper Cover.......................................................................... 4-2
1.1.2. Removing the Front Cover ........................................................................... 4-6
1.1.3. Installing the Upper Cover ............................................................................ 4-7
2. Keyboard Assembly ................................................................................................. 4-8
2.1. Removing the Keyboard............................................................................................. 4-8
2.2. Installing the Keyboard............................................................................................... 4-9
3. Ink Jet Printer Assembly.........................................................................................4-10
3.1. Removing the Printer Assembly ............................................................................... 4-11
3.2. Installing the Printer Assembly.................................................................................. 4-11
3.3. Disassembling the Printer Assembly......................................................................... 4-12
3.3.1. Removing the CA Unit................................................................................ 4-13
3.3.2. Installing the CA Unit.................................................................................. 4-13
3.3.3. Disassembling the PF Unit.......................................................................... 4-14
3.3.3.1. Removing the Form.............................................................................. 4-15
3.3.3.2. Removing the Release Lever and Release Shaft.................................. 4-16
3.3.3.3. Removing the ACF Shaft Assembly...................................................... 4-17
3.3.3.4. Removing the Pressure Rollers and Roller Holders............................... 4-18
3.3.3.5. Removing the Holder Plate................................................................... 4-19
3.3.3.6. Removing the Hopper Assembly........................................................... 4-20
3.3.3.7. Disassembling the Paper Feed Assembly ............................................. 4-22
3.3.3.8. Removing the Eject Roller Assembly and the PF Roller Assembly........ 4-23
3.3.3.9. Removing the Motor Frame Assembly.................................................. 4-24
3.3.3.10. Removing the PF Stopper..................................................................... 4-25
3.3.3.11. Removing the PE Sensor...................................................................... 4-26
3.3.4. Disassembling the CA Unit ......................................................................... 4-27
3.3.4.1. Removing the Carriage......................................................................... 4-28
3.3.4.2. Removing the Carriage Drive................................................................ 4-30
3.3.4.3. Removing the Star Wheel Holder Assembly ......................................... 4-31
3.3.4.4. Removing the MS Holder Assembly...................................................... 4-32
3.3.4.5. Removing the Leaf Switch (Home Position Sensor).............................. 4-33
3.3.4.6. Removing and Mounting the KB Switch Assy........................................ 4-34
3.4. Adjusting the CA Unit ............................................................................................... 4-35
3.4.1. Adjusting the Carriage Home Position......................................................... 4-35
3.4.2. Adjusting Belt Tension................................................................................ 4-36

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4. Removing the FDD Assembly ................................................................................4-39
5. Switch PCB ............................................................................................................ 4-40
5.1. Removing the Switch PCB ....................................................................................... 4-41
5.2. Installing the Switch PCB.......................................................................................... 4-41
6. Removing the Main PCB........................................................................................4-42
7. Removing the Shield Plate (ESD) .......................................................................... 4-43
CHAPTER 5 MONITOR REPAIR AND ADJUSTMENT (MODEL CT-1450).............. 5-1
1. Safety Precautions...................................................................................................5-1
2. Theory of Operation................................................................................................. 5-3
2.1. Video Process ............................................................................................................ 5-3
2.2. Video Amplifier........................................................................................................... 5-3
2.3. Vertical Circuitry......................................................................................................... 5-4
2.4. Horizontal Sync and Drive.......................................................................................... 5-4
2.5. Horizontal Output Transistor....................................................................................... 5-5
2.6. High Voltage and Focus ............................................................................................. 5-5
3. Adjustment and Servicing......................................................................................... 5-6
3.1. Test Pattern................................................................................................................ 5-6
3.2. Measurement Conditions............................................................................................ 5-7
3.2.1. Display Dimension Measurement.................................................................. 5-7
3.2.2. Raster Centering & Tilt Adjustment (see Fig. 5.3) ......................................... 5-7
3.3. Adjustments ............................................................................................................... 5-8
3.3.1. B+ Voltage Adjustments: None required. ..................................................... 5-8
3.3.2. Horizontal Adjustments................................................................................. 5-8
3.3.3. Vertical Adjustments (see Fig. 5.5) ............................................................... 5-9
3.3.4. Brightness & Contrast................................................................................... 5-9
3.3.5. Focus Adjustment......................................................................................... 5-9
3.3.6. Raster Geometry Adjustments.................................................................... 5-10
3.3.6.1. Pin Cushion/Barrel Correction (top, bottom and sides) Adjustment........ 5-10
3.3.6.2. Trapezoidal Correction (corners) Adjustment ........................................ 5-12
4. Troubleshooting .....................................................................................................5-13
5. Control Parts Location............................................................................................5-14
6. Monitor Block Diagram........................................................................................... 5-15
CHAPTER 6 MAINTENANCE .................................................................................... 6-1
1. Lubrication................................................................................................................ 6-1
1.1. Lubricants................................................................................................................... 6-1
1.2. Precautions ................................................................................................................ 6-1
1.3. Lubrication Points....................................................................................................... 6-1

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2. Replacing the Ink Cartridge......................................................................................6-5
3. Cleaning the Print Head...........................................................................................6-9
3.1. Cleaning the Print Head Automatically........................................................................ 6-9
3.2. Cleaning the Ink Jet Nozzles and Contacts................................................................. 6-9
3.3. Cleaning the Bracket Contacts (Carriage)................................................................. 6-10
APPENDIX A SPECIFICATIONS...........................................................................APP-1
1. Electrical System.................................................................................................APP-1
2. Printing................................................................................................................APP-2
3. Keyboard.............................................................................................................APP-4
4. Monitor (CT-1450)...............................................................................................APP-4
5. Environmental Tolerance ....................................................................................APP-5
6. Dimensions & Weight..........................................................................................APP-6

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FIGURES
Figure Title Page
Fig. 1.1 Ink Jet Printer Assembly....................................................................................... 1-1
Fig. 1.2 General View of Printing Mechanism .................................................................... 1-3
Fig. 1.3A Paper Feed Mechanism........................................................................................ 1-4
Fig. 1.3B Paper Feed Mechanism........................................................................................ 1-5
Fig. 1.4 Paper Eject System.............................................................................................. 1-5
Fig. 1.5 Paper Setting System........................................................................................... 1-6
Fig. 1.6 Printer Flat Cable to Main PCB............................................................................. 1-7
Fig. 1.7 Printer Flat Cable to Cartridge Alignment.............................................................. 1-8
Fig. 1.8 Ink Jet Cartridge to Flat Cable Alignment.............................................................. 1-9
Fig. 1.9 Carriage Motion Control...................................................................................... 1-10
Fig. 1.10 Print Maintenance Operation - Spitting................................................................ 1-12
Fig. 1.11 Print Maintenance Operation - Wiping................................................................. 1-13
Fig. 1.12 Print Maintenance Operation - Capping .............................................................. 1-14
Fig. 1.13 Carriage Home Position Sensor.......................................................................... 1-15
Fig. 1.14 PE Sensor Mechanism....................................................................................... 1-16
Fig. 1.15 Keyboard Assembly............................................................................................ 1-18
Fig. 1.16 Key Top/Key Stem Assembly ............................................................................. 1-19
Fig. 1.17 LCD Unit Installation in the Upper Cover............................................................. 1-21
Fig. 1.18 LCD of DP-525CJ/LW-800ic............................................................................... 1-22
Fig. 1.19 LCD of DP-530CJ/LW-810ic and LW-810icBL .................................................... 1-23
Fig. 1.20 LCD of DP-540CJ, DP-550CJ/LW-840ic............................................................. 1-24
Fig. 2.1 Major Electronic Component Parts........................................................................ 2-2
Fig. 2.2 Power Supply Circuit ............................................................................................ 2-4
Fig. 2.3 Timing Chart of +24V Generation Circuit............................................................... 2-5
Fig. 2.4 Timing Chart of +5V Generation Circuit ................................................................ 2-5
Fig. 2.5 Reset Circuit......................................................................................................... 2-6
Fig. 2.6 Buzzer Drive Circuit.............................................................................................. 2-8
Fig. 2.7 Country & Model Specification Change-over Circuit.............................................. 2-9
Fig. 2.8 RS-232C I/F Circuit ............................................................................................ 2-10
Fig. 2.9 Ink Jet Head Drive Circuit................................................................................... 2-11

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ii
Figure Title Page
Fig. 2.10 Carriage Motor Drive Circuit................................................................................ 2-12
Fig. 2.11 Line Feed Motor Drive Circuit ............................................................................. 2-13
Fig. 2.12 Carriage Home Position Sensor Circuit............................................................... 2-14
Fig. 2.13 PE Sensor Detection Circuit ............................................................................... 2-14
Fig. 2.14 External View of the Switch PCB........................................................................ 2-15
Fig. 2.15 Switch PCB Circuit ............................................................................................. 2-15
Fig. 2.16 Key/FPC Operation ............................................................................................ 2-16
Fig. 2.17 Electrode Wiring................................................................................................. 2-17
Fig. 2.18 Keyboard Control Circuit..................................................................................... 2-18
Fig. 2.19 Keyboard Matrix ................................................................................................. 2-19
Fig. 2.20 Keyboard Symbols (Corresponding to Keyboard Matrix in Fig. 2.19)................... 2-19
Fig. 2.21 LCD Display Operation Block Diagram................................................................ 2-20
Fig. 2.22 Example of Control Signal Timing Chart.............................................................. 2-21
Fig. 2.23 LCD Drive Voltage Generation Circuit (Minus Voltage VEE)................................ 2-22
Fig. 2.24 LCD Drive Voltage Generation Circuit (Plus Voltage VEE).................................. 2-22
Fig. 2.25 CFL Backlight Circuit.......................................................................................... 2-23
Fig. 2.26 FDD Block Diagram............................................................................................ 2-25
Fig. 3.1 Troubleshooting Flowchart.................................................................................... 3-4
Fig. 3.2 Troubleshooting Flowchart (continued) ................................................................. 3-5
Fig. 3.3 Serial Number Entry Display............................................................................... 3-14
Fig. 3.4 Self-Print Pattern................................................................................................ 3-15
Fig. 3.5 Results of Self-Print Test.................................................................................... 3-17
Fig. 3.6 Self-Test Menu................................................................................................... 3-18
Fig. 3.7 LCD Test Menu.................................................................................................. 3-20
Fig. 3.8 CHECK Test Display (magnified)........................................................................ 3-21
Fig. 3.9 CROSS Test Display (magnified)........................................................................ 3-22
Fig. 3.10 BLACK Test Display........................................................................................... 3-23
Fig. 3.11 DISP Q Test Display (magnified)........................................................................ 3-24
Fig. 3.12 Slant Line Test Display (magnified)..................................................................... 3-25
Fig. 3.13 Printer Check #1 (in progress) Display................................................................ 3-26
Fig. 3.14 Diagram of Print Test Pattern 1 .......................................................................... 3-27
Fig. 3.15 Sample Print Test Pattern 1................................................................................ 3-28

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Figure Title Page
Fig. 3.16 Printer Check #2 (in progress) Display................................................................ 3-29
Fig. 3.17 Sample Test Pattern 2........................................................................................ 3-30
Fig. 3.18 Dot Patterns for Print Test #2 (Patterns 1 to 4)................................................... 3-31
Fig. 3.19 Dot Patterns for Print Test #2 (Patterns 5 and 6) ................................................ 3-32
Fig. 3.20 Keyboard Test #1 Display................................................................................... 3-33
Fig. 3.21 Keyboard Test Key Locations............................................................................. 3-33
Fig. 3.22 FDD Test (in progress) Display........................................................................... 3-36
Fig. 3.23 Special FDD Test Display 1................................................................................ 3-37
Fig. 3.24 Special FDD Test Display 2................................................................................ 3-38
Fig. 3.25 Special FDD Test (in progress) Display .............................................................. 3-38
Fig. 3.26 Special FDD Test Display 1................................................................................ 3-41
Fig. 3.27 FDD Write Error Rate Check Display.................................................................. 3-42
Fig. 3.28 FDD Read Error Rate Check Display.................................................................. 3-44
Fig. 3.29 PE Sensor Test Start Display 1 .......................................................................... 3-46
Fig. 3.30 PE Sensor Test Start Display 2 .......................................................................... 3-46
Fig. 3.31 CR Test Start Display 1...................................................................................... 3-47
Fig. 3.32 Self-Test Menu (DISK TYPE Setting) ................................................................. 3-48
Fig. 3.33 RS232C Echo-Back Test Start Display............................................................... 3-49
Fig. 4.1 Cover Assemblies................................................................................................. 4-1
Fig. 4.2 Removing the Sub Paper Support and Paper Support .......................................... 4-3
Fig. 4.3 Removing the Top Cover...................................................................................... 4-4
Fig. 4.4 Removing the Upper Cover................................................................................... 4-5
Fig. 4.5 Removing the Core............................................................................................... 4-8
Fig. 4.6 Removing the LCD Unit........................................................................................ 4-9
Fig. 4.7 Removing the LCD Lower Cover......................................................................... 4-10
Fig. 4.8 Removing the LCD PCB (1)................................................................................ 4-12
Fig. 4.9 Removing the LCD PCB (2)................................................................................ 4-13
Fig. 4.10 Removing the LCD PCB (3)................................................................................ 4-14
Fig. 4.11 Removing the LCD PCB (4)................................................................................ 4-15
Fig. 4.12 Removing the LCD PCB (5)................................................................................ 4-16
Fig. 4.13 Removing LCD Latch and LCD Plate.................................................................. 4-17
Fig. 4.14 Installing LCD Latch............................................................................................ 4-19

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Figure Title Page
Fig. 4.15 Fitting LCD Volume Guide to LCD Volume Knob................................................. 4-21
Fig. 4.16 Installing the LCD Lower Cover........................................................................... 4-22
Fig. 4.17 Fitting the Core .................................................................................................. 4-23
Fig. 4.18 Installing the Hinge Assy..................................................................................... 4-24
Fig. 4.19 Removing the Keyboard Assembly ..................................................................... 4-25
Fig. 4.20 Installing the Keyboard ....................................................................................... 4-26
Fig. 4.21 Removing the Carrying Handle........................................................................... 4-27
Fig. 4.22 Ink Jet Printer Assembly..................................................................................... 4-28
Fig. 4.23 Disassembling the Printer Assembly................................................................... 4-30
Fig. 4.24 Construction of the PF Unit................................................................................. 4-32
Fig. 4.25 Removing the Form............................................................................................ 4-33
Fig. 4.26 Removing the Release Lever and Release Shaft from the PF Base Assembly.... 4-34
Fig. 4.27 Removing the ACF Shaft Assembly.................................................................... 4-35
Fig. 4.28 Removing the Pressure Rollers and Roller Holders............................................. 4-36
Fig. 4.29 Removing the Holder Plate................................................................................. 4-37
Fig. 4.30 Removing the Hopper Assembly......................................................................... 4-39
Fig. 4.31 Disassembling the Paper Feed Assembly........................................................... 4-40
Fig. 4.32 Removing the Eject Roller Assembly and the PF Roller Assembly...................... 4-41
Fig. 4.33 Removing the Motor Frame Assembly................................................................ 4-42
Fig. 4.34 Removing the PF Stopper................................................................................... 4-43
Fig. 4.35 Removing the PE Sensor.................................................................................... 4-44
Fig. 4.36 Construction of the CA Unit ................................................................................ 4-45
Fig. 4.37 Printer Mechanism.............................................................................................. 4-46
Fig. 4.38 Removing the Carriage....................................................................................... 4-47
Fig. 4.39 Removing the Carriage Drive.............................................................................. 4-48
Fig. 4.40 Removing the Star Wheel Holder Assembly........................................................ 4-49
Fig. 4.41 Removing the MS Holder Assembly.................................................................... 4-50
Fig. 4.42 Removing the Leaf Switch (Home Position Sensor) ............................................ 4-51
Fig. 4.43 Removing and Mounting the KB Switch Assy...................................................... 4-52
Fig. 4.44 Adjusting the Belt Tension.................................................................................. 4-55
Fig. 4.45 Measuring Friction during Carriage Movement.................................................... 4-56
Fig. 4.46 Removing the FDD Assembly............................................................................. 4-57

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Figure Title Page
Fig. 4.47 Switch PCB........................................................................................................ 4-58
Fig. 4.48 Switch PCB........................................................................................................ 4-59
Fig. 4.49 Removing the Main PCB..................................................................................... 4-60
Fig. 4.50 Removing the Shield Plate (ESD)....................................................................... 4-61
Fig. 5.1 Carriage Assembly Lubrication Points................................................................... 5-2
Fig. 5.2 Paper Feed Assembly Lubrication Points.............................................................. 5-3
Fig. 5.3 Eject Roller Assembly and PF Roller Assembly Lubrication Points........................ 5-4
Fig. 5.4 Open the Paper Support and Top Cover and
Tilting the LCD to the Uprige Position ................................................................... 5-6
Fig. 5.5 Removing the Ink Jet Cartridge............................................................................. 5-7
Fig. 5.6 Removing the Protection Tape.............................................................................. 5-7
Fig. 5.7 Placing the Cartridge in the Carriage .................................................................... 5-8
Fig. 5.8 Fitting the Cartridge in the Carriage ...................................................................... 5-8
Fig. 5.9 Cleaning the Bracket Contacts............................................................................ 5-11
TABLES
Table 1.1 Summary of Maintenance Operations................................................................. 1-11
Table 2.1 Clock Circuit......................................................................................................... 2-8
Table 2.2 Table of LCD Modules........................................................................................ 2-21
Table 2.3 FDC(#5) and FDD Module Links (Interface Signals)............................................ 2-24
Table 3.1 Failure Analysis.................................................................................................... 3-6
Table 3.2 FDD Special Test Error Stage Codes ................................................................. 3-39
Table 3.3 FDD Special Test Error Codes............................................................................ 3-40
Table 5.1 Recommended Lubricants.................................................................................... 5-1

THEORY
SERVICE MANUAL Mechanical
1-1
PART I THEORY OF OPERATION
CHAPTER 1 MECHANICAL THEORY
1. Ink Jet Printer
Fig. 1.1 Ink Jet Printer Assembly

THEORY
Mechanical SERVICE MANUAL
1-2
1.1. Ink Jet Printer System Configuration
The ink jet printer contains the following components:
• Carriage assembly
• Carriage motion control system
• Paper feed mechanism
• Maintenance station
• Sensors
The outline of these components are described below.
1. Carriage Assembly
The carriage assembly consists of the carriage and ink cartridge (the cartridge
contains the ink jet nozzles). The carriage consists of the head locker and locker
spring, the rubber pad, and the flat cable.
2. Carriage Motion Control System
The carriage motion control system consists of the carriage motor, motor pulley,
timing belt, idle pulley, and the idle pulley holder and holder spring.
3. Paper Feed Mechanism
The paper feed mechanism consists of the paper feed system, paper eject system,
and the paper setting system.
4. Maintenance Station
The maintenance station consists of the MS holder, the MS carriage assembly
(carriage, rubber cap, plunger, compression spring, and extension spring), the wiper,
and the felt form ink absorbers (in spitting trough and under carriage assembly ).
5. Sensors
There are two sensors in the printer assembly: the carriage home position sensor
(attached to the top right end of the CA frame) and the paper end sensor (attached to
the bottom of the PF base at the right rear).

THEORY
SERVICE MANUAL Mechanical
1-3
Fig. 1.2 General View of Printing Mechanism

THEORY
Mechanical SERVICE MANUAL
1-4
1.2. Ink Jet Operation
1.2.1. Paper Feed Mechanism
The paper feed mechanism consist of the paper feed system, paper eject system, and
the paper setting system.
(1)The paper feed system consists of the ACF shaft gear, separate roller, ACF shaft
locker, locker spring, idle gears 1, 2, 3, and 4, PF roller gear, changer lever 1 and 2,
spring, and the line feed motor.
Paper feed system ACF(Auto cut-sheet feeder)
When the paper feed motor is driven in the opposite direction (reverse rotation) of the
paper feeding, the change lever 1 moves to engage the ACF shaft gear via the idle
gear. The separate roller rotates in the paper separation direction (normal rotation)
and separates a sheet of paper. The separate roller rotates with paper feeding
operation and returns to the initial position. Separated paper is fed to contact PF
roller and the pressure roller by the separate roller where the top of the paper is
registered.
Fig. 1.3A Paper Feed Mechanism

THEORY
SERVICE MANUAL Mechanical
1-5
Fig. 1.3B Paper Feed Mechanism
(2)The paper eject system consists of the line feed motor, collar, idle gears 1, 5, and 6,
PF roller gear, eject roller gear, pressure roller, roller holder, holder plate, pressure
roller spring, star wheel holder, and the star wheel.
After paper is registered, the paper feed motor is driven in the paper feeding direction
(normal rotation) and paper is fed by the PF roller and the pressure roller. After
printing paper is ejected by the eject roller and star wheel.
Fig. 1.4 Paper Eject System

THEORY
Mechanical SERVICE MANUAL
1-6
(3)The paper setting system consists of the hopper, hopper spring, separate pad, collar,
paper guide, ACF change lever, change spring, and the ACF change shaft.
When inserting a thick paper, the ACF change lever should place at the front
position.
24lb Thick Paper
Envelope
Label
Transparency etc.
Fig. 1.5 Paper Setting System

THEORY
SERVICE MANUAL Mechanical
1-7
1.2.2. Carriage Assembly
The carriage assembly consists of the carriage and ink cartridge (the cartridge contains
the ink jet nozzles). The carriage consists of the head locker and locker spring, the
rubber pad, and the flat cable. The flat cable connects to the main PCB. See Fig. 1.6.
The printer flat cable must be firmly in contact with the ink jet cartridge for printing to be
enabled. The flat cable is located in the carriage by four alignment pins; proper
alignment of the cartridge to the cable is established in three datums (reference
planes/points): X, Y, and Z. When the cartridge is installed in the carriage, the flat cable
contacts are compressed against the cartridge contacts by the rubber pad. See Figs.
1.7 and 1.8.
Fig. 1.6 Printer Flat Cable to Main PCB

THEORY
Mechanical SERVICE MANUAL
1-8
Fig. 1.7 Printer Flat Cable to Cartridge Alignment