Service manual
Table Of Contents
- Revision Table
- Introduction
- Chapter 1
- Features and General Specifications
- Chapter 2
- Mechanism Configuration and Operating Principles
- Printer Mechanism Operating Principles
- Print mechanism unit
- Print head unit movement
- Wire movement when a single dot is printed
- Printing a character (9x9 font)
- Paper Feed Mechanism Unit
- Paper loading (semi-automatic loading)
- Paper feeding
- Ribbon Feed Mechanism Unit
- Ribbon feeding
- Detection Mechanism Unit
- Home position detection mechanism
- Paper detection mechanism
- Paper roll near-end detection mechanism (optional)
- Auto-cutter mechanism
- Ribbon Switch Mechanism Unit
- Electrical Circuitry Operating Principles
- Principles of Operation
- Printer Mechanism Driver Circuits
- Printer Mechanism Operating Principles
- Chapter 3
- Handling and Maintenance
- Chapter 4
- Troubleshooting
- Chapter 5
- Disassembly, Assembly, and Adjustment
- Small Part Specifications
- Disassembly
- Sub-assembly A
- Main Assembly 1
- Main Assembly 2
- Main Assembly 3
- Main Assembly 4
- Main Assembly 5
- Main Assembly 6
- Main Assembly 7
- Main Assembly 8
- Main Assembly 9
- Main Assembly 10
- Main Assembly 11
- Main Assembly 12
- Main Assembly 13
- Main assembly 14
- Main Assembly 15
- Main Assembly 16
- Main Assembly 17
- Main Assembly 1 (Case Unit)
- Main Assembly 2 (Case Unit)
- Main Assembly 3 (Case Unit)
- Main Assembly 4 (Case Unit)
- Main Assembly 5 (Case Unit)
- Main Assembly 6 (Case Unit)
- Main Assembly 7 (Case Unit)
- Main Assembly 8 (Case Unit)
- Main Assembly 9 (Case Unit)
- Main Assembly 10 (Case Unit)
- Main Assembly 11 (Case Unit)
- Main Assembly 12 (Case Unit)
- Adjustment
- Appendix
- Appendix
- Addendum 1
- Main Circuit Board Types and Maintenance
- Addendum 2
- Lower Plate Change and ROM Spacer Abolition
- Addendum 3
- Auto-Cutter Release Tab Change

4-8 Troubleshooting Rev. B
Confidential
6
Replace printer
End
OK?
No
Replace interface PCB.
No
No
No
No
No
No
Yes
No
Yes
Yes
Yes
Yes
Set DIP switch 1–1 to OFF.
Send data from host to printer.
Is “?” printed?
Are serial
interface parameters
set to identical values at
host and printer?
Make settings identical.
Replace with a proper cable.
Is
Connect the interface
End
End
End
End
OK?
OK?
OK?
6 Data from host is not printed normally.
Yes
Does
interface
cable match
specifications?
Yes
connected to the
main PCB
firmly?
interface PCB
PCB firmly.
mechanism assembly
Yes
(*)
(*) Dotted line indicates
the process of checking
problems for the serial
interface.