Epson 750 3.4 Repair of the Control Board

EPSON Stylus Photo 750 Revision A

Troubleshooting Repair of the Control Board 45

3.4 Repair of the Control Board

This section describes the problems related to the power supply board. The table below provides vari ous symptoms, likely causes, and checkpoints.

The checkpoints refer to waveforms, resistance, and other values to check to evaluate the operation of each component.

Table 3-7. Repair of the Control Board Table 3-8. Repair of the Control Board

Sympto

mCondition Cause Check point Solution

The

printer

does not

operate at

all.

CPU does

not work.

Reset

circuit is

broken.

Check +5VDC line(Pin 7 of IC8) and

reset signal (Pin 2 of IC8).

Replace

IC8.

ROM is not

selected

correctly.

Check that the waveform of Pin 11

of IC3 reverses High/Low. Replace

T1.

RAM is

broken. Replace

Q1.

CPU is

broken.

Check the signal waveform Pin 88

of IC1.

Contents

Main Notice PRECAUTIONS DANGER About This Manual Contents Symbols Used in This Manual Page Stylus Photo 750 Revision A 1 Table of Contents Product Description Operating Principles Troubleshooting Disassembly and Assembly Maintenance Appendix Page Product Description Overview 4 1.1 Overview 1.1.1 General Characteristics Product Description General Description 5 1.2 General Description 1.2.1 Printing Product Description General Description 6 1.2.2 Paper Feeding 1.2.3 Paper Specification Product Description General Description 7 1.2.4 Printable Area Figure 1-3. Printable Area Cut Sheet The figure below shows printable area. PW BM 1.2.5 Adjust Lever Settings 1.2.6 Environmental Conditions Product Description General Description 10 1.2.7 Ink Cartridge 1.2.7.1 Black Ink Cartridge 1.2.7.2 Color Ink Cartridge Product Description General Description 11 1.2.8 Input Data Buffer 1.2.9 Electric Specification 1.2.10 Reliability 1.2.11 Safety Approvals 1.2.12 Acoustic noise 1.2.13 CE Marking 1.2.14 Printer Language and Emulation 1.2.14.1 ESC/P Control Codes Page Product Description Parallel Interface 14 1.3 Parallel Interface 1.3.1 Parallel Interface(Forward channel) Product Description Parallel Interface 15 NOTE:In/Out refers to the direction of signal flow from the printers point of view. 1.3.2 Parallel Interface(Reverse channel) Product Description Parallel Interface 16 Table 1-9. Connect pin assignment and signals Page Product Description Parallel Interface 18 1.3.3 Serial Interface NOTE:In/Out refers to the direction of signal flow from the printers point of view. Product Description Parallel Interface 19 1.3.4 USB(Universal Serial Bus) Interface 1.3.5 Prevention of data transfer time-out on the host 1.3.6 Interface selection 1.3.7 IEEE 1284.4 protocol Product Description Function 21 1.4 Function 1.4.1 Control Code 1.4.2 Bi-directional Command 1.4.3 Control Panel 1.4.3.1 Switches 1.4.4 Special Setting Mode NOTE:*Waste ink counter value and Timer IC counter value are initialized. 1.4.5 LED Indications Product Description Function 23 1.4.6 Errors Product Description Function 24 1.4.7 Initialization Product Description Function 25 1.4.8 Initialization Setting 1.4.9 Physical Specification Page Page Operating Principles Overview 28 2.1 Overview 2.1.1 Printer Mechanism Operating Principles Overview 29 Operating Principles Operating Principles of Electric Circuit 30 2.2 Operating Principles of Electric Circuit 2.2.1 C257 PSB Power Supply Circuit Operating Principles Operating Principles of Electric Circuit 31 TRANS(T1) Operating Principles Operating Principles of Electric Circuit 32 2.2.2 C259 Main Control Circuit Figure 2-4. Control Circuit Block Diagram 2.2.2.1 Major Elements Major elements used in C259 main control circuit board are below. Table 2-2. Major Elements Operating Principles Operating Principles of Electric Circuit 33 2.2.2.2 Reset Circuit Operating Principles Operating Principles of Electric Circuit 34 2.2.2.3 Sensor Circuit Operating Principles Operating Principles of Electric Circuit 35 2.2.2.4 Timer Circuit op08 op07 ORG Figure 2-8. Common Drive Circuit 2.2.2.7 Paper Feed (Pump) Motor (PF/Pump Motor) Drive Circuit +5 - + 6 5 C90A05 (IC1) 2.2.2.8 Carriage Motor(CR Motor) Drive Circuit op10 CN7 Rotor 1 Page Troubleshooting Overview 39 3.1 Overview Figure 3-1. Troubleshooting Flowchart Table 3-1. Motor, Coil Resistance Table 3-2. Sensor Check Point Troubleshooting Overview 40 Table 3-3. Error Indication Troubleshooting Unit Level Troubleshooting 41 3.2 Unit Level Troubleshooting Figure 3-2. Flowchart 1 1. Printer does not operate. Page Troubleshooting Unit Level Troubleshooting 43 4. Paper feed operation is not performed correctly Figure 3-6. Flowchart 5 Figure 3-5. Flowchart 4 5. Abnormal Control Panel 3.3 Unit Repair (Power Supply Board) EPSON Stylus Photo 750 Revision A Troubleshooting Repair of the Control Board 45 3.4 Repair of the Control Board Troubleshooting Repair of the Control Board 46 Table 3-9. Repair of the Control Board Troubleshooting Unit Repair (Printer Mechanism) 47 3.5 Unit Repair (Printer Mechanism) Table 3-11. Repair of the Printer Mechanism Troubleshooting Unit Repair (Printer Mechanism) 48 Table 3-12. Repair of the Printing Mechanism Table 3-13. Repair of the Printing Mechanism Troubleshooting Unit Repair (Printer Mechanism) 49 Table 3-14. Repair of the Printer Mechanism Table 3-15. Repair of the Printer Mechanism Page Disassembly and Assembly Overview 51 4.1 Overview 4.1.1 Precautions Disassembly and Assembly Overview 52 4.1.3 Work Completion Check Disassembly and Assembly Disassembly 53 4.2 Disassembly Figure 4-1. Flowchart The flowchart below shows step-by step disassembly procedures. START Housing Removal 4.2.1 Housing Removal Disassembly and Assembly Disassembly 55 4.2.2 Circuit Boards Removal NOTE:When removing C257PSB, disconnect cables connected to the C259 main board. Disassembly and Assembly Disassembly 56 Disassembly and Assembly Disassembly 57 4.2.3 Control Panel Removal Disassembly and Assembly Disassembly 58 4.2.4 Absorber Tray, Assembly;A Removal Disassembly and Assembly Disassembly 59 4.2.5 Printer Mechanism Removal 4.2.5.1 Print Head Removal Page Disassembly and Assembly Disassembly 61 4.2.5.2 Pump, Assembly/Cap, Assembly Removal Disassembly and Assembly Disassembly 62 Disassembly and Assembly Disassembly 63 4.2.5.3 Motor, Assembly, CR Removal Disassembly and Assembly Disassembly 64 4.2.5.4 Motor Assembly PF Removal Disassembly and Assembly Disassembly 65 4.2.5.5 ASF, Assembly Removal Disassembly and Assembly Disassembly 66 4.2.5.6 Paper Feed Roller Assembly Removal Disassembly and Assembly Disassembly 67 4.2.5.7 Roller Assembly, LD Left/Right Removal Disassembly and Assembly Disassembly 68 4.2.5.8 Carriage Assembly Removal Disassembly and Assembly Disassembly 69 Page Disassembly and Assembly Disassembly 71 4.2.5.10 Roller, Assembly, PF Removal Disassembly and Assembly Disassembly 72 Page Disassembly and Assembly Disassembly 74 4.2.5.12 Cartridge Sensor(Sensor, I/C) Removal Disassembly and Assembly Disassembly 75 Page Adjustment Overview 77 5.1 Overview 5.1.1 Required Adjustment Adjustment Adjustment 78 5.2 Adjustment 5.2.1 Paper Gap Adjustment Adjustment Adjustment 79 Adjustment Adjustment by Adjustment Program 80 5.3 Adjustment by Adjustment Program 5.3.1 Adjustment Program 5.3.1.1 How to use the Adjustment Program Adjustment Adjustment by Adjustment Program 81 Adjustment Adjustment by Adjustment Program 82 5.3.2 Setting Destination Information Adjustment Adjustment by Adjustment Program 83 5.3.3 Head Voltage ID Adjustment Adjustment Adjustment by Adjustment Program 84 5.3.4 Head Angular Adjustment Adjustment Adjustment by Adjustment Program 85 Adjustment Adjustment by Adjustment Program 86 5.3.5 Bi-D Adjustment Adjustment Adjustment by Adjustment Program 87 5.3.6 Head Cleaning Adjustment Adjustment by Adjustment Program 88 5.3.7 Initial Ink Charge Adjustment Adjustment by Adjustment Program 89 5.3.8 Counter Value for Ink Absorber 5.3.8.1 Protect Counter Value 5.3.8.2 Protect Counter Reset Page Maintenance Overview 91 6.1 Overview 6.1.1 Cleaning 6.1.2 Service Maintenance Maintenance Overview 92 6.1.3 Lubrication Table 6-1. Specified Lubricants Table 6-2. Lubrication Point Maintenance Overview 93 Table 6-3. Lubrication Point Table 6-4. Lubrication Point Page Page Page Appendix Connector Summary 97 7.1 Connector Summary Table 7-2. Connector CN4 Figure 7-1. Connection of the Major Components 7.1.1 Major Component Unit Table 7-1. Connector Summary for C259Main Appendix Connector Summary 98 Table 7-3. Connector CN5 Table 7-7. Connector CN9 Table 7-5. Connector CN7 Table 7-4. Connector CN6 Appendix Connector Summary 99 Table 7-8. Connector CN9 Table 7-9. Connector CN10 Table 7-10. Connector CN11 Page Page Appendix Exploded Diagram 102 7.3 Exploded Diagram Figure 7-5. Exploded Diagram-1 Following pages shows exploded diagram of Stylus Photo 750. EXPLODED DIAGRAM FOR EPSON STYLUS PHOTO 750 (1/3)