OKIDATA Microline ML395C User manual

Page: 1
Service Guide ML395/395C
Chapter 0 About This Manual
ML395 // ML395C
Dot Matrix Printers
Adobe Acrobat printable reference
copy of the OKIDATA Service Training Manual.
09/17/97
Note: This Adobe Acrobat version of the Okidata Service Training Manual was built with the
pictures rendered at 300 dpi, which is ideal for printing, but does not view on most
displays well.
Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business
Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com)

Table of Contents Page
Service Guide ML395/395C
0 About This Manual
Front Cover 1
....Manual Copyright 2
1 Product Specifications
1.1 Overview - General Information 3
1.2 Product Specifications 4
1.3 Paper Specifications 5
1.4 Physical Specifications 6
1.5 Power Requirements 7
1.6 Environmental Conditions 8
1.7 Agency Approvals 9
1.8 Options 10
1.9 Consumables 11
1.10 Memory Specifications 12
1.11 Printer Reliability 13
2 Principles of Operation
2.1Electrical Operation - General Information 14
....2.1.02 Microprocessors (MPUs) and Peripheral Circuits 15
....2.1.03 Initialization 16
....2.1.04 Interface Control 17
....2.1.05 Printhead Drive Circuit 18
....2.1.06 Spacing Drive Circuit 19
....2.1.07 Line Feed Circuit 20
....2.1.08 Alarm Circuits 21
....2.1.09 Paper End Detection Circuit 22
....2.1.10 Power Supply 23
2.2 Mechanical Operation 24
....2.2.02 Spacing 25
....2.2.03 Ribbon Drive 26
....2.2.04 Paper Feed 27
....2.2.05 Paper-End Detection 28
....2.2.06 Automatic Paper Loading 29
....2.2.07 Paper Park 30
3 Maintenance & Disassembly
3.1Maintenance - General Information 31
....3.1.02 Maintenance Items 32
....3.1.03 Maintenance Precautions 33
3.2 Disassembly/Assembly Procedures - General Information 34
....3.2.01 Preliminary Items Printhead 35
....3.2.02 Ribbon Guide 36
....3.2.03 Ribbon Protector 37
....3.2.04 Upper Cover Assembly 38

Table of Contents Page
....3.2.05 Operator Panel Assembly 39
....3.2.06 Control Board (TFCB) 40
....3.2.07 Interface Connector Board (TFIF or LQPN) 41
....3.2.08 Printer Mechanism 42
....3.2.09 Platen Assembly 43
....3.2.10 Line Feed Motor 44
....3.2.11 Head Cable Assembly 45
....3.2.12 Sensor Board 46
....3.2.13 Ribbon Feed Assembly 47
....3.2.14 Space Motor Assembly 48
....3.2.15 Space Belt 49
....3.2.16 Cooling Fan 50
....3.2.17 Bail/Ribbon Motor Assembly 51
....3.2.18 Paper Bail Assembly 52
....3.2.19 Carriage and Carriage Shaft 53
....3.2.20 Paper Pressure Guide 54
....3.2.21 Printhead Gap / Release Lever Microswitches 55
....3.2.22 Push Tractor Assembly 56
....3.2.23 Power Supply Unit 57
....3.2.24 Ribbon Shift Arm Spring / Ribbon Shift Arm 58
....3.2.25 Roller Lever 59
....3.2.26 Ribbon Guide 60
....3.2.27 Bail Open Cam and Bail Open Gear 61
....3.2.28 Ribbon Shift Cam and Ribbon Shift Gear 62
....3.2.29 Ribbon Shift Cam Lever Assembly 63
....3.2.30 Printer Unit 64
....3.2.31 BTFD Printed Circuit Board 65
....3.2.32 Tension Spring 66
....3.2.33 Sheet Guide 67
....3.2.34 BTF Front Door Assembly 68
....3.2.35 Drive Pulley and Mini-pitch Belt 69
....3.2.36 Line Feed Motor 70
....3.2.37 Tractor Assembly 71
3.3 Printer Adjustments - Printhead Gap 72
....3.3.02 Line Feed Belt Tension 73
....3.3.03 Color Adjustment (Microline 395C Printer) 74
....3.3.04 Key Combinations 75
....3.3.05 Menu Operation - Menu Mode 76
........Menu Print 77
........Sample Menu 78
........Menu Settings 79
........Menu Reset 80
........Limited Operation 81
....3.3.06 Top of Form 82

Table of Contents Page
....3.3.07 Paper Park 83
....3.3.08 Forms Tear Off 84
3.4 Cleaning 85
3.5 Lubrication 86
........Lubrication Points (Monochrome and Color) 87
............Lubrication Points (Monochrome and Color) -
Continued 88
............Lubrication Points (Monochrome and Color) -
Continued 89
........Lubrication Points (Color) 90
........Lubrication Points (Options) 91
3.6 Shipping Instructions - Return For Service 92
....3.6.02 All Other Returns 93
4 Failure & Repair Analysis
4.1 Overview 94
....4.1.02 Printer Serial Number Identification 95
4.2 Reporting Problems - General Information 96
....4.2.02 Problem Lists 97
....4.2.03 Reporting Methods 98
4.3 Troubleshooting Updates - General Information 99
....4.3.02 Okilink II 100
....4.3.03 Faxable Facts 101
....4.3.04 Technical Service Bulletins 102
4.4 Troubleshooting Tips - Preliminary Checks 103
....4.4.02 Problem Categories 104
....4.4.03 START HERE Flowchart 105
....4.4.04 Tips for Preventing Image Problems 106
....4.4.05 Common Problems 107
4.5 Abnormal Output 108
4.6 Fault Alarms - General Information 109
4.7 Repair Analysis Procedures (RAPS) - Using The RAPS 110
....4.7.02 RAP Index 111
........RAP 01: Power Lamp Does Not Light 112
........RAP 02: Space Error (ALARM 5B) 113
........RAP 03: Head Homing Error (ALARM 53) 114
........RAP 04: Ribbon Homing Error (ALARM 57) 115
........RAP 05: Bail Home Error (ALARM 5C) 116
........RAP 06: Wrong Character, Character Omission, or Dot
Omission 117
........RAP 07: Ribbon Feed Trouble 118
........RAP 08: Line Feed Trouble 119
........RAP 09: Malfunction of Operator Panel Switch 120
........RAP 10A: Data Receive Failure 121
........RAP 10B: Parallel Interface Problem 122

Table of Contents Page
........RAP 10C: Serial Interface Problem 123
........RAP 10D: Data Receive Failure (Alarm Light Lit) 124
........RAP 11: Color Ribbon Shift Problem 125
4.8 Printer Tests 126
....4.8.02 Font Test 127
....4.8.03 Serial Interface - Loopback Test 128
....4.8.04 Hexadecimal Dump 129
4.9 Resistance Checks - General Information 130
....4.9.02 Printhead Resistance Check 131
....4.9.03 Line Feed Motor Resistance Check 132
....4.9.04 Space Motor Resistance Check 133
....4.9.05 Ribbon Motor Resistance Check 134
A Board Diagrams
A.1 Overview - General Information 135
A.2 Index To Charts 136
....A.2.01 Main Controller Board (TFCB) 137
............ML395/395C Jumper Plugs SP2 : Jim
Fitzpatrick/Project Leader/Okidata; 11/18/96 138
....A.2.02 Power Supply Board (POW) 139
....A.2.03 Interface Board (TFIF) 140
............Change sp102 jumper : Eric
Tomenga/OKI_ELECTRIC/US 141
............Shorting Plug SP102 : Jim Fitzpatrick/Project
Leader/Okidata; 11/18/96 142
....A.2.04 Sensor Board (LQEW) 143
....A.2.05 Operator Panel (TFOP) 144
B Illustrated Parts Listing
B1.1 Overview - General Information 145
....B.1.02 Definition of Terms 146
....B.1.03 Parts Ordering Information 147
B.2 Charts 148
....B.2.01 Upper Cover Assembly 149
....B.2.02 Printer Unit General Assembly 150
....B.2.03 Operator Panel 151
....B.2.04 Carriage Assembly (Black and White) 152
....B.2.05 Carriage Assembly (Color) 153
....B.2.06 Printer Unit - Black and White (1 of 3) 154
....B.2.07 Printer Unit - Black and White (2 of 3) 155
....B.2.08 Printer Unit - Black and White (3 of 3) 156
....B.2.09 Printer Unit - Color (1 of 3) 157
....B.2.10 Printer Unit - Color (2 of 3) 158
....B.2.11 Printer Unit - Color (3 of 3) 159
....B.2.12 Cables and Connectors 160
....B.2.13 Options 161

Table of Contents Page
....B.2.14 Pull Tractor Assembly (Option) 162
....B.2.15 Bottom Tractor Feed Unit (Push) [BTF] (Option) 163
....B.2.16 BTF Pull-Up Roller Assembly (Option) 164
....B.2.17 Consumables 165
....B.2.18 Packing Materials 166
....B.2.19 Documentation 167

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Service Guide ML395/395C
Chapter 0 About This Manual
This document may not be reproduced without the written permission of the Okidata ® Technical Training
Group. Every effort has been made to ensure the accuracy of the information contained in this training
course. Okidata is not responsible for errors beyond its control.
© 1994 by Okidata All rights reserved.
First Edition May, 1993 P/N 59260501
Second Edition October, 1994 P/N 59260502
Written and produced by the Okidata Technical Training Group
Please send any comments on this publication to the address listed below.
Technical Training Group
Okidata
532 Fellowship Road
Mount Laurel, NJ 08054-3499
Okilink Login Name: Technical Training
OKI is a registered trademark of Oki Electric Industry Company, Ltd.; marques deposee de Oki Electric
Industry Company, Ltd.; marca registrada, Oki Electric Industry Company, Ltd.
OKIDATA is a registered trademark of Oki Electric Industry Company, Ltd.; marques deposee de Oki
Electric Industry Company, Ltd.; marca registrada, Oki Electric Industry Company, Ltd.
MICROLINE is a registered trademark of Oki Electric Industry Company, Ltd.; marque depose de Oki
Electric Industry Company, Ltd.
Centronics is a registered trademark of the Centronics Data Computer Corp.
Epson is a registered trademark of Seiko Epson Corporation.
IBM is a registered trademark of International Business Machine Corporation.
Microsoft is a registered trademark of Microsoft Corporation.
MS-DOS is a registered trademark of Microsoft Corporation.
PC is a registered trademark of International Business Machine Corporation.
Proprinter is a registered trademark of International Business Machine Corporation.
Windows is a trademark of Microsoft Corporation
Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business
Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com)

Page: 3
Service Guide ML395/395C
Chapter 1 Product Specifications
1.1 OVERVIEW
1.1.01 General Information
The Microline 395 is a high speed, dot matrix printer, which utilizes a 24 wire printhead. The Microline 395
comes standard with both an RS232-C Serial Interface and a Centronics Parallel Interface. The printer is
available in either a standard version (Microline 395; single color output) or a color capable version
(Microline 395C; multiple color output). The Microline 395 is capable of emulating the Epson LQ 850/1050
or the IBM Proprinter XL24 printers. The Microline 395C emulates the Epson LQ 2550, Epson
LQ850/1050 or the IBM Proprinter XL24.
Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business
Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com)

Page: 4
Service Guide ML395/395C
Chapter 1 Product Specifications
1.2 PRODUCT SPECIFICATIONS
1.2.01 Paper Feed Method
Built-in push tractor
Friction feed
1.2.02 Paper Path
Bottom Feed
Rear Feed
Top Feed
1.2.03 Printhead Type
Staggered, 24 pin, stored energy printhead
1.2.04 Interface Methods
Both are Standard
Centronics Parallel Interface
RS232-C Serial Interface
1.2.05 Print Speed
Pitch Head Gap
Setting High Speed Draft Utility Near Letter Quality Letter Quality
10 cpi 1,2 405 cps 202 cps 135 cps
12 cpi 1,2 607 cps 486 cps 242 cps 162 cps
15 cpi 1,2 607 cps 303 cps 202 cps
17.1 cpi 1,2 347 cps 231 cps
20 cpi 1,2 405 cps 270 cps
10 cpi 3+ 352 cps 175 cps 117 cps
12 cpi 3+ 422 cps 211 cps 140 cps
15 cpi 3+ 528 cps 263 cps 175 cps
17.1 cpi 3+ 528 cps 300 cps 200 cps
20 cpi 3+ 352 cps 234 cps
cpi - Characters Per Inch
cps - Characters Per Second

1.2.06 Symbol Sets
Standard ASCII
Epson Character Set
IBM Character Set I and Set II
IBM Proprinter All Character Set
International Characters
Line Graphics
Code Page 850, 863,437
1.2.07 Standard Fonts
Utility (Used in Utility and High Speed Draft Modes)
Courier
Swiss
Roman
Orator
1.2.08 Line Feed Increments
1/6" n/180"
1/8" n/216"
n/60" n/360"
n/72"
1.2.09 Line Feed Time
55 ms @ 6 LPI
8.0 IPS (inches per second) slew rate @ gap 1,2
6.0 IPS (inches per second) slew rate @ gap 3+
1.2.10 Paper Out Detection
Printhead distance from edge of paper when End of Paper is detected
Rear Feed: 5.8"
Bottom Feed: 2.4"
Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business