LQ-670 Service Manual
Rev. A
5-14
5.4 Repairing the Main Board
Refer to the following table for repairing the main board.
Symptom
Condition
Cause
Checkpoint
Solution
The printer does
not work at all.
Reset signal is
not canceled.
Defective
operation of the
reset circuit
After the power is turned on,
check 1pin of IC12 stays
LOW for a while.
•
Reset signal is generated in
the IC21 and sent to the
CPU and gate array.
Replace the main
board.
VOUT signal is
output.
Check if +5V is normal and
also check pin 7 and pin 8 of
CN3.
Replace the
power supply
board
CPU does not
work.
Clock signal is
not generated.
Check the signal of pin 26
and 27 in the IC11 (clock
signal of CPU)
Figure 5-11.Clock Signal of
CPU
Replace the main
board or CRU1.
PROM(IC8) or
Flash
ROM(IC7) is
defective.
Check the waveform of 22
pin of IC 7 or IC8.
•
If there is no waveform,
gate array(IC10) is defective.
Figure 5-12. Chip Select
Signal
Replace the main
board.
Table 5-11. Repairing the C214 Main Board
Содержание LQ 670 - B/W Dot-matrix Printer
Страница 1: ...EPSON IMPACT DOT MATRIX PRINTER EPSON LQ 670 SERVICE MANUAL SEIKO EPSON CORPORATION 4007875 ...
Страница 5: ...v REVISION SHEET Revision Issued Data Contents Rev A May 28 1997 First issue ...
Страница 114: ...Chapter 6 Maintenance 6 1 Preventive Maintenance 6 1 ...
Страница 116: ...LQ 670 Service Manual Rev A 6 2 Figure 6 1 Lubrication Points ...
Страница 122: ...LQ 670 Service Manual Rev A A 5 A 2 Circuit Diagram Figure A 2 C214Main Board Circuit Diagram ...
Страница 123: ...Appendix Rev A A 6 Heat Sink Q1 D51 Figure A 3 C214PSB Board Circuit Diagram ...
Страница 124: ...LQ 670 Service Manual Rev A A 7 Heat Sink Q1 D51 Figure A 4 C214PSE Board Circuit Diagram ...
Страница 125: ...Appendix Rev A A 8 A 3 Component Layout Figure A 5 C214 Main Board Component Layout ...
Страница 126: ...LQ 670 Service Manual Rev A A 9 Figure A 6 C214 PSB Board Component Layout Figure A 7 C214 PSE Board Component Layout ...
Страница 127: ...Appendix Rev A A 10 A 4 Exploded Diagram Figure A 8 Exploded Diagram ...
Страница 128: ...LQ 670 Service Manual Rev A A 11 Figure A 9 Exploded Diagram ...
Страница 129: ...Appendix Rev A A 12 Figure A 10 Exploded Diagram ...
Страница 135: ...EPSON SEIKO EPSON CORPORATION ...