Epson Stylus Color 300 User manual

EPSON TERMINAL PRINTER
EPSON Stylus Color 300
SERVICE MANUAL
EPSON
4007996

 All rights reserved. No part of this manual may be reproduced, stored in a retrieval
system, or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, without the prior written permission of SEIKO
EPSON CORPORATION.
 The contents of this manual are subject to change without notice.
 All effort have been made to ensure the accuracy of the contents of this manual.
However, should any errors be deteced, SEIKO EPSON would greatly appreciate being
informed of them.
 The above not withstanding SEIKO EPSON CORPORATION can assume no
responsibility for any errors in this manual or the consequences thereof.
EPSON is a registered trademark of SEIKO EPSON CORPORATION.
General Notice: Other product names used herein are for identification purpose only
and may be trademarks or registered trademarks of their respective
owners. EPSON disclaims any and all rights in those marks.
Copyright © 1996 SEIKO EPSON CORPORATION. Printed in Japan.

PRECAUTIONS
Precautionary notations throughout the text are categorized relative to 1)Personal injury and
2) damage to equipment.
DANGER Signals a precaution which, if ignored, could result in serious or fatal personal
injury. Great caution should be exercised in performing procedures preceded
by DANGER Headings.
WARNING Signals a precaution which, if ignored, could result in damage to equipment.
The precautionary measures itemized below should always be observed when performing
repair/maintenance procedures.
DANGER
1. ALWAYS DISCONNECT THE PRODUCT FROM THE POWER SOURCE AND
PERIPHERAL DEVICES PERFORMING ANY MAINTENANCE OR REPAIR
PROCEDURES.
2. NOWORK SHOULD BE PERFORMED ON THE UNIT BY PERSONS UNFAMILIER
WITH BASIC SAFETY MEASURES AS DICTATED FOR ALL ELECTRONICS
TECHNICIANS IN THEIR LINE OF WORK.
3. WHEN PERFORMING TESTING AS DICTATED WITHIN THIS MANUAL, DO NOT
CONNECT THE UNIT TO A POWER SOURCE UNTIL INSTRUCTED TO DO SO.
WHEN THE POWER SUPPLY CABLE MUST BE CONNECTED, USE EXTREME
CAUTION IN WORKING ON POWER SUPPLY AND OTHER ELECTRONIC
COMPONENTS.
WARNING
1. REPAIRS ON EPSON PRODUCT SHOULD BE PERFORMED ONLY BY AN EPSON
CERTIFIED REPAIR TECHNICIAN.
2. MAKE CERTAIN THAT THE SOURCE VOLTAGES IS THE SAME AS THE RATED
VOLTAGE, LISTED ON THE SERIAL NUMBER/RATING PLATE. IF THE EPSON
PRODUCT HAS A PRIMARY AC RATING DIFFERENT FROM AVAILABLE POWER
SOURCE, DO NOT CONNECT IT TO THE POWER SOURCE.
3. ALWAYS VERIFY THAT THE EPSON PRODUCT HAS BEEN DISCONNECTED FROM
THE POWER SOURCE BEFORE REMOVING OR REPLACING PRINTED CIRCUIT
BOARDS AND/OR INDIVIDUAL CHIPS.
4. IN ORDER TO PROTECT SENSITIVE MICROPROCESSORS AND CIRCUITRY, USE
STATIC DISCHARGE EQUIPMENT, SUCH AS ANTI-STATIC WRIST STRAPS, WHEN
ACCESSING INTERNAL COMPONENTS.
5. REPLACE MALFUNCTIONING COMPONENTS ONLY WITH THOSE COMPONENTS
BY THE MANUFACTURE; INTRODUCTION OF SECOND-SOURCE ICs OR OTHER
NONAPPROVED COMPONENTS MAY DAMAGE THE PRODUCT AND VOID ANY
APPLICABLE EPSON WARRANTY.

PREFACE
This manual describes basic functions, theory of electrical and mechanical operations,
maintenance and repair procedures of EPSON Stylus Color 300. The instructions and
procedures included herein are intended for the experienced repair technicians, and
attention should be given to the precautions on the preceding page. The chapters are
organized as follows:
CHAPTER 1. PRODUCT DESCRIPTIONS
Provides a general overview and specifications of the product.
CHAPTER 2. OPERATING PRINCIPLES
Describes the theory of electrical and mechanical operations of the product.
CHAPTER 3. TROUBLESHOOTING
Provides the step-by-step procedures for troubleshooting.
CHAPTER 4. DISASSEMBLY AND ASSEMBLY
Describes the step-by-step procedures for disassembling and assembling the product.
CHAPTER 5. ADJUSTMENTS
Provides Epson-approved methods for adjustment.
CHAPTER 6. MAINTENANCE
Provides preventive maintenance procedures and the lists of Epson-approved lubricants and
adhesives required for servicing the product.
APPENDIX
Provides the following additional information for reference:
• Connector pin assignments
• Electric circuit boards components layout
• Exploded diagram
• Electrical circuit boards schematics

REVISION SHEET
Revision Issued Contents
A July 2, 1997 First issue

TABLE OF CONTENTS
CHAPTER 1.PRODUCT DESCRIPTIONS
CHAPTER 2.OPERATION PRINCIPLES
CHAPTER 3.DISASSEMBLY AND ASSEMBLY
CHAPTER 4.ADJUSTMENT
CHAPTER 5.TROUBLESHOOTING
CHAPTER 6.MAINTENANCE
APPENDIX

CHAPTER 1
PRODUCT DESCRIPTIONS
1.1 FEATURES ...................................................................................... 1-1
1.2 SPECIFICATIONS ........................................................................... 1-2
1.2.1 Printing Specifications.......................................................... 1-2
1.2.2 Software Specifications........................................................ 1-3
1.2.3 Paper Handling ...................................................................... 1-4
1.2.4 Paper Specifications ............................................................. 1-4
1.2.5 Printable Area ........................................................................ 1-6
1.2.6 PG Adjust Lever Setting........................................................ 1-7
1.2.7 Paper Select Lever Setting ................................................... 1-7
1.2.8 Ink Cartridge Specification................................................... 1-8
1.2.9 Electrical Specifications ....................................................... 1-9
1.2.10 Environmental Conditions.................................................. 1-9
1.2.11 Reliability............................................................................ 1-10
1.2.12 Acoustic Noise................................................................... 1-10
1.2.13 Safety Approvals................................................................ 1-10
1.2.14 CE Marking......................................................................... 1-10
1.2.15 Physical Specifications..................................................... 1-11
1.3 INTERFACE SPECIFICATION......................................................1-12
1.4 OPERATIONS................................................................................ 1-12
1.4.1 Control Panel ....................................................................... 1-12
1.4.1.1 Buttons.......................................................................1-12
1.4.1.2 LED Indicators ........................................................... 1-14
1.5 MAIN COMPONENTS ................................................................... 1-15
1.5.1 Printer Mechanism .............................................................. 1-15
1.5.2 Main Control Board (C224 MAIN Board)............................1-15
1.5.3 Power Supply Unit (C160 PSB/PSE Board)....................... 1-15
1.5.4 Housing ................................................................................ 1-15

Chapter 1 Product Descriptions
Rev. A 1-1
1.1 FEATURES
The EPSON Stylus Color 300 printer is a color ink jet printer that comes with standard four
colors (Black and CMY) printhead. The major features of this printer are:
 Standard four-colors printing.
Both black and color (CMY) print nozzles are built in one-piece printhead.
 High-quality color printing
360 dpi (Horizontal/Vertical) printing and semi-720 dpi (Vertical only) printing
 High-speed printing
200 CPS at 10CPI (Pica) text printing in Black color.
 Standard Bi-directional Parallel Interface (IEEE1284 Nibble mode)

EPSON Stylus Color 300 Service Manual
Rev. A
1-2
1.2 SPECIFICATIONS
This section describes the product specifications for EPSON Stylus Color 300.
1.2.1 Printing Specifications
Print system: On-demand ink jet printer
Nozzle configuration: Black: 31 nozzles
(11 nozzles x 2 columns and 10 nozzles x 1 column)
Color: 11 nozzles / color
#B30 #29
#31
#B3
#B2 #B1
#C1
#M1
#Y1
#C11 #M11 #Y11
1/180"
(0.1411mm) 1/60"
(0.4233mm)
1/180"
(0.1411mm)
1/180"
(0.1411mm)
1/180"
(0.1411mm)
1/60"
(0.4233mm)
16/360"
(1.1289mm)
104/360"
(7.3378mm)
104/360"
(7.3378mm)
16/360"
(1.1289mm)
16/360"
(1.1289mm)
Print direction (Paper feed)
Viewed from the back of the printhead
Figure 1-1. Printhead Nozzle Configuration
Print direction: Bi-directional printing with logical-seeking
Print speed: Text: 200 CPS (LQ/10CPI in Black color)
Graphics: 20 IPS (at 360DPI)
Printable column: Text: 80 columns (10CPI)
Graphics: 2880 dot (at 360DPI)
Character Table: No table and include only the following characters:
 Alphabet [A to Z] (code 41H ~ 5AH)
 Number [0 to 9] (code 30H ~ 39H)
 SPACE (code 20H)
 Symbol [#] (code 23H)
Typeface: Bitmap LQ / EPSON Courier (10CPI)
Input data buffer: 25Kbyte

Chapter 1 Product Descriptions
Rev. A 1-
3
1.2.2 Software Specifications
Printer Language: Exclusive control codes for EPSON Stylus Color 300
EPSON Remote Command
Control Code: <Character mode>
General operation: Initialize printer ESC @
Paper feeding: Form feed FF
Line feed LF
Carriage operation Carriage return CR
EEPROM Control ESC |
<Graphics mode>
General operation: Initialize printer ESC @
Uni-directional printing ESC U
CSF Mode control ESC EM
Paper feeding: Form feed FF
Line feed LF
Line spacing ESC +
Carriage operation: Carriage return CR
Page formatting: Page length ESC (C
Top/Bottom margin ESC (c
Print position control: Horizontal print position ESC $, ESC ¥
Vertical print position ESC (V, ESC (v
Spacing: Define unit ESC (U
Graphics: Graphics mode ESC (G
Raster graphics ESC . (∗1)
Color control: Printing color ESC r (∗2)
Note) EPSON Stylus Color 300 requires the specific printer driver for proper printing
operation and control, and use of other printer driver could result in improper
printing.
∗1: Works only with unique parameters.
∗2: It works only as a print buffer select command.

EPSON Stylus Color 300 Service Manual
Rev. A
1-4
1.2.3 Paper Handling
Feeding method: Friction feed with built-in ASF
Paper path: Rear-top entrance / Front eject
Line spacing: 1/6 inch or programmable in 1/360 inch minimum increments.
Paper feeding speed: 102 mS (at 1/6 inch paper feed pitch)
1.2.4 Paper Specifications
 Cut sheet
 Size:
Table 1-1. Paper Size - Cut Sheet
Type Width Length
A4 210 mm
(8.3”) 297 mm (11.7”)
LETTER 216 mm
(8.5”) 279 mm (11.0”)
B5 182 mm
(7.2”) 257 mm (10.1”)
LEGAL 216 mm
(8.5”) 356 mm (14.0”)
Statement 139.7 mm
(5.5”) 215.9 mm (8.5”)
Executive 184.2 mm
(7.25”) 266.7 mm (10.5”)
 Thickness: 0.08 ~ 0.11 mm (0.003 ~ 0.004”)
 Weight: 64 ~ 90 g/m² (17 ~ 24 lb.)
 Quality: Plain paper, Recycled paper, EPSON special medias
 Envelope
 Size:
Table 1-2. Paper Size - Envelope
Type Width Length
No.10 241 mm
(9 1/2”) 104.8 mm
(4 1/8”)
DL 220 mm
(8.7”) 110 mm (4.3”)
 Thickness: 0.16 ~ 0.52 mm (0.006 ~ 0.020”)
 Weight: 45 ~ 90 g/m²
 Quality: BOND paper, Plain paper, Airmail
Note) ∗Envelope printing is allowed only under normal temperature/humidity
condition.
∗Set the longer side of envelope horizontally at setting.

Chapter 1 Product Descriptions
Rev. A 1-
5
 Others
 Size:
Table 1-3. Paper Size - Special Media
Type Width Length
Transparency (A4) 210 mm
(8.3”) 297 mm (11.7”)
Transparency (LETTER) 216 mm
(8.5”) 279 mm (11.0”)
Glossy Paper (A4) 210 mm
(8.3”) 297 mm (11.7”)
Glossy Paper (LETTER) 216 mm
(8.5”) 279 mm (11.0”)
Index Card (A6 size) 105 mm
(4.1”) 148 mm (5.8”)
 Quality: Exclusive transparency/Glossy Paper
 Thickness: 0.23 mm (0.0091”) for Index Card
Note) Set the paper thickness lever to “THICK PAPER” position for index card
printing.

EPSON Stylus Color 300 Service Manual
Rev. A
1-6
1.2.5 Printable Area
The maximum printable area with each type of paper is summarized in table below.
Table 1-4. Printable Area
Type PW
(typ.) PL (typ.) LM (Min.) RM (Min.) TM (Min.) BM (Min.)
A4 210 mm
(8.3”) 297 mm (11.7”) 3.0 mm (0.12”) 3.0 mm (0.12”) 3.0 mm (0.12”) 14.0 mm (0.55”)
LETTER 216 mm
(8.5”) 279 mm (11.0”) ⇑⇑⇑⇑
LEGAL 216 mm
(8.5”) 356 mm (14”) ⇑⇑⇑⇑
A6 105 mm
(4.1”) 148 mm (5.8”) ⇑⇑⇑⇑
B5 182 mm
(7.2”) 257 mm (10.1”) ⇑⇑⇑⇑
Statement 139.7 mm
(5.5”) 215.9 mm (8.5”) ⇑⇑⇑⇑
Executive 184.2 mm
(7.25”) 266.7 mm (10.5”) ⇑⇑⇑⇑
No.10 241 mm
(9.5”) 105 mm (4.1”) ⇑33.8 mm (1.33”) ⇑⇑
DL 220 mm
(8.7”) 110 mm (4.3”) ⇑13.8 mm (0.54”) ⇑⇑
Printable Area
PW
LM RM
TM
PL
BM
CUT SHEET
PW
LM RM
PL
TM
BM
ENVELOPE
Printable Area
Figure 1-2. Printable Area

Chapter 1 Product Descriptions
Rev. A 1-
7
1.2.6 PG Adjust Lever Setting
The paper-gap (PG); a space between the printhead nozzle surface annd the paper
surface, can be adjusted to the appropriate level by the PG adjust lever which located
underneath the printer cover.
Table 1-5. PG Adjust Lever Setting
Paper Type Lever Position Gap Setting
Cut Sheet Front
(“0” position) 0 mm
Envelope Rear
(“+” position) +0.62 mm
1.2.7 Paper Select Lever Setting
The built-in ASF is equipped with the adjust lever and the position of lever should be set to
appropriate position according to the type of paper used for the printing.
Table 1-6. Paper Select Lever Setting
Paper Feeding Paper Type
Source Select
Lever
Position
Cut Sheet Envelope
ASF Thick No OK
Normal OK No
Manual Thick OK OK
Insertion Normal No No
Paper Thickness Lever
(Forward position: Normal
Backward position: Thick paper)
Paper Thickness Lever (Locate underneath the printer cover)
(Forward position: "0" Normal
Backward position: "+" Envelopes)
Figure 1-3. PG Adjust Lever and Paper Select Lever

EPSON Stylus Color 300 Service Manual
Rev. A
1-8
1.2.8 Ink Cartridge Specification
Type: Exclusive cartridge
Color: Black and CMY (Cyan, Magenta, Yellow)
Print capacity: 220 pages (360 DPI / 5% duty for each color on A4)
450 pages (ISO/IEC10561 LETTER pattern at 360 DPI
monochrome printing on A4)
Validity: 2 years (in sealed package)
6 months (out of package)
Storage conditions: Transit (Package): -30 ∼60 °C
(120 hours or less at 60 °C and
a month or less at 40 °C)
Storage (Package): -30 ∼40 °C
(A month or less at 40 °C)
After installation: -20 ∼40 °C
(A month or less at 40 °C)
Weight: 69.3 gram (internal ink amount = 41.1g)
Dimensions: 45.9 (W) ×56.5 (D) ×38.5 ±0.3 (H) mm
56.5 mm
38.5 mm
45.9 mm
Black
Cyan
Magenta
Yellow
Figure 1-4. Ink Cartridge

Chapter 1 Product Descriptions
Rev. A 1-
9
1.2.9 Electrical Specifications
Table 1-7. Electrical Specification
Item 120V Version 220 ∼240V Version
Rated Voltage 120 VAC 220 ∼240 VAC
Input Voltage
Range 103.5 ∼132 V 198 ∼264 V
Rated Frequency
Range 50 ∼60 Hz 50 ∼60 Hz
Input Frequency
Range 49.5 ∼60.5 Hz 49.5 ∼60.5 Hz
Rated Current 0.5 A
(Max. 0.5 A) 0.3 A (Max. 0.3 A)
Power
Consumption Approx. 15 W (ISO/IEC10561 LETTER pattern) Approx. 15 W (ISO/IEC10561 LETTER pattern)
Energy Star Compliant
Insulation
Resistance 10 MΩ, Min.
(applying 500 VDC between AC
line and chassis)
10 MΩ, Min.
(applying 500 VDC between AC
line and chassis)
Dielectric
Strength AC 1000 Vrms for 1 min. or AC 1200 Vrms for 1 sec.
(between AC line and chassis)
AC 1500 Vrms for 1 min.
(between AC line and chassis)
1.2.10 Environmental Conditions
Table 1-8. Environmental Conditions
Condition Operating Non operating
Temperature 10 ∼35 °C ∗3 -20 ∼60 °C ∗1
Humidity 20 ∼80 % ∗2/3 5 ∼85 % ∗1/2
Shock
Resistance 1G (within 1 ms) 2G
(within 2 ms) ∗1
Vibration
Resistance 0.15G 0.50G ∗1
Note) ∗1: Applicable when the unit is in a shipping container.
∗2: Without condensation.
∗3: The unit should be operated within the range shown in figure below.
10 27 35
80
55
20
Humidity
(%)
Temperature
(°C)
Figure 1-5. Temperature and Humidity Range

EPSON Stylus Color 300 Service Manual
Rev. A
1-10
1.2.11 Reliability
Total Print Volume: 10,000 pages (A4 / LETTER)
Printhead Life: 1000 million dots / nozzle (Black and CMY)
1.2.12 Acoustic Noise
Level: Approx. 45 dB(A) (according to ISO7779)
1.2.13 Safety Approvals
Table 1-9. Safety Approvals
Item 120V Version 220 ∼240V Version
Safety Standard UL1950 with D3
CSA C22.2 No.950 with D3 EN 60950 (TÜV, NEMKO)
EMI FCC part 15 subpart B class B
CSA C108.8 class B EN55022 (CISPR Pub.22) class B AS/NSZ 3548 class B
1.2.14 CE Marking
[220 ~ 240V Version only]
Low Voltage Directive 73/26/EEC: EN60950
EMC Directive89/336/EEC: EN55022 Class B
EN61000-3-2
EN61000-3-3
EN50082-1
IEC801-2
IEC801-3
IEC801-4

Chapter 1 Product Descriptions
Rev. A 1-11
1.2.15 Physical Specifications
Dimensions: 397 (W) × 319 (D) × 269 (H) mm
(operating condition)
Weight: 3.9 Kg (exclude the printhead and the ink cartridge)
269 mm
397 mm
319 mm
Figure 1-6. Dimensions

EPSON Stylus Color 300 Service Manual
Rev. A
1-12
1.3 INTERFACE SPECIFICATION
Refer to the service manual of EPSON Stylus Color 200 / Stylus 200 for details.
1.4 OPERATIONS
This section describes the basic operation of the printer.
1.4.1 Control Panel
The control panel is equipped with two non-lock type push buttons and three LED
indicators, and operations of each button and LED indicator are described below.
LOAD/EJECT
CLEANING
Buttons
LED Indicators
POWER (Green)
INK OUT (Red)
PAPER OUT (Red)
Figure 1-7. Control Panel
1.4.1.1 Buttons
 Normal Operation
Table 1-10. Control Panel - Normal Operations
Button Operation Function
LOAD/EJECT Pressed less than
3 sec. •Loads or ejects the paper.
•When the carriage is at the ink-cartridge
replace position, return the carriage to the
home position.
Pressed for 3 sec. •Starts the ink-cartridge replace operation and
the carriage moves to the ink-cartridge
replace position.
CLEANING Pressed less than
3 sec. •Starts the cleaning operation.
•When the printer is in “Ink Low”, “Ink Out” or
“No ink cartridge” status, the printer moves the
carriage to the ink-cartridge replace position.
Pressed for 3 sec. •When the carriage is at the ink-cartridge
replace position, return the carriage to the
home position.

Chapter 1 Product Descriptions
Rev. A 1-1
3
 Power-On Operation
Table 1-11. Control Panel - Power-on Operations
Button Function
[1
st
button]
Hold down at
power on
[2
nd
button]
Pressed within
3 sec. after
power on. ∗2
The printer perform the following after
performing the control panel operation
in left column.
CLEANING ----- Self-printing test
LOAD/EJECT ----- Status printing
LOAD/EJECT
+
CLEANING
LOAD/EJECT
+
CLEANING ∗1
EEPROM Initialization
Note) ∗1: Holds down the specified buttons for 10 sec. or more until INK OUT and
PAPER OUT LED starts blinking.
∗2: After the power on, INK OUT and PAPER OUT LED starts blinking and
continue for about 3 sec. “Press within 3 sec. after power on” means to press
2
nd
buttons while these LED are blinking.
 Self-test printing:The printer prints the self check test pattern. The printer prints
a page at a time and pauses between each page. When the
printer is in pause state, press LOAD/EJECT button to resume
printing and turn the power off to cancel the self-test printing.
 Status printing: The printer prints; Firmware version, ink counter value and a
nozzle check pattern. The printer goes to a pause state after
print one page. To cancel the status printing, turn the power
off while the printer is in pause state.
 EEPROM Initialization: Initialize the following addresses of the EEPROM (refer to the
EEPROM address map table in Appendix.)
1AH: Interface selection (00H: Auto)
1BH: Interface Wait Time (02H: 2 sec.)
2CH/2DH: Counter A (Protect counter) (00H)
70H - 73H: 4-color head non-installation time (00H)
78H - 7BH: Power Off Timer (00H)