Epson LQ-300 + Service Manual page 7

3.1 Overview ........................................................................................... 45
3.2 Troubleshooting .............................................................................. 46
3.2.1 Initialization Check .................................................................... 46
3.2.2 Check Performance By Self-Check Function ............................ 46
3.2.2.1 Indicator LEDs .................................................................... 46
3.2.3 Identify Problems From Symptoms ........................................... 47
3.2.4 Unit and Parts Check ................................................................ 49
3.2.4.1 Printhead Check ................................................................. 50
3.2.4.2 Motor Check ....................................................................... 51
3.2.4.3 Sensor Check ..................................................................... 51
3.2.4.4 Printhead Driver Check ...................................................... 52
Chapter 4 Disassembly and Assembly
4.1 Overview ........................................................................................... 54
4.1.1 Precautions ............................................................................... 54
4.1.2 Tools .......................................................................................... 54
4.1.3 Service Checks After Repair ..................................................... 55
4.2 Disassembly and Assembly ........................................................... 56
4.2.1 Printhead Removal .................................................................... 57
4.2.2 Upper Housing Removal ........................................................... 58
4.2.3 Printer Mechanism Removal ..................................................... 59
4.2.4 Board Assembly and Panel Removal ........................................ 60
4.2.5 C395 MAIN Board Assembly Removal ..................................... 60
4.2.6 C294PSB/PSE Board Assembly Removal ................................ 61
4.2.7 Printer Mechanism Disassembly ............................................... 62
4.2.7.1 CR Motor Assembly Removal ............................................ 62
4.2.7.2 Platen Removal .................................................................. 63
4.2.7.3 Carriage Unit Removal ....................................................... 64
4.2.7.4 Ribbon Feed Mechanism Removal .................................... 65
4.2.7.5 RPE Sensor Removal ........................................................ 66
4.2.7.6 BPE Sensor Removal ......................................................... 66
4.2.7.7 HP Sensor Removal ........................................................... 66
4.2.7.8 PG Sensor Removal ........................................................... 67
4.2.7.9 Release Lever Position Sensor Removal ........................... 67
4.2.7.10 PF Motor Assembly Removal ........................................... 68
4.2.7.11 Paper Feed Mechanism Disassembly .............................. 68
4.2.7.12 Paper Guide Removal ...................................................... 70
Chapter 5 Adjustment
5.1 Overview .......................................................................................... 72
5.1.1 Platen Gap Adjustment ............................................................. 72
5.1.2 Bi-D Adjustment ........................................................................ 73
Chapter 6 Maintenance
6.1 Maintenance ..................................................................................... 78
6.1.1 Cleaning .................................................................................... 78
6.1.2 Lubrication ................................................................................. 78
Chapter 7 Appendix
7.1 Connector Summary ....................................................................... 83
7.2 Parts List .......................................................................................... 87
7.3 Exploded Diagrams ......................................................................... 90
7.4 Component Layout ......................................................................... 93
7.5 Electric Circuit Schematics ............................................................ 97