5.4 REPAIRING C165 PSB/PSE BOARD ASSEMBLY
This section provides instructions to repair a defective power supply board assembly. It describes various
symptoms, likely causes, and checkpoints. Checkpoints refer to proper waveforms, resistances, and other
values to check when evaluating the operation of any potentially faulty component. Check these values
and take the appropriate action.
Note:
This information is necessary only for servicers who repair to the component level. Servicers who
repair to the unit level (including all servicers in the U.S.) can ignore this section.
WARNING
The
OPERATE
switch on the control panel only turns the secondary power circuit on or off, so
the primary circuit is live as long as the printer is connected to an AC power outlet. Before, you
repair or touch the power supply board, be sure to disconnect the AC power outlet.
Table 5-6. Repairing the C165 PSB/PSE Board Assembly
Problem
Cause
Checkpoint
Solution
The 35 V and
5 V lines are
not output
when the
printer is
powered on.
The diode bridge DB1
is dead.
Measure the DC voltage between the pins
3 and 4 of the DB1.
Replace
the DB1.
^
The transformer coil is
open.
Measure the resistance of T1 transformer
coils at pins 12-15, 9-11, 7-8, 3-4.
Replace
the T1.
^
Q1 is dead.
Check that the resistance between the
source and drain is infinite.
Check the voltage waveform between
the source and drain of the Q1.
Replace
the Q1.
PC1 is dead.
Check the voltage waveform between
pins 3 and 4 of the PC1.
Replace
PC1.
Troubleshooting
LQ-2170 Service Manual
5-10
Rev. A
Summary of Contents for LQ-2170
Page 1: ...EPSON TERMINAL PRINTER LQ 2170 SERVICE MANUAL EPSON 4005735 ...
Page 5: ...REVISION SHEET Revision Issued Date Revision Page Rev A December 5 1995 1st issued ...
Page 11: ...Figure 1 1 Exterior View of the LQ 2170 Product Description LQ 2170 Service Manual 1 2 Rev A ...
Page 80: ......
Page 127: ...1 Abnormal CR Operation LQ 2170 Service Manual Troubleshooting Rev A 5 5 ...
Page 141: ...LQ 2170 Service Manual Troubleshooting Rev A 5 19 ...
Page 156: ...Appendix LQ 2170 Service Manual A 10 Rev A ...
Page 158: ...Appendix LQ 2170 Service Manual A 12 Rev A ...
Page 159: ...Figure A 3 C165 PSB Board Assembly Circuit Diagram LQ 2170 Service Manual Appendix Rev A A 13 ...
Page 160: ...Appendix LQ 2170 Service Manual A 14 Rev A ...
Page 161: ...Figure A 4 C165 PSE Board Assembly Circuit Diagram LQ 2170 Service Manual Appendix Rev A A 15 ...
Page 162: ...Appendix LQ 2170 Service Manual A 16 Rev A ...
Page 167: ...Figure A 9 LQ 2170 Exploded Diagrams 2 LQ 2170 Service Manual Appendix Rev A A 21 ...
Page 168: ...Figure A 10 LQ 2170 Exploded Diagrams 3 Appendix LQ 2170 Service Manual A 22 Rev A ...
Page 169: ...Figure A 11 C S F Bin1 Exploded Diagrams 1 LQ 2170 Service Manual Appendix Rev A A 23 ...
Page 170: ...Figure A 12 C S F Bin1 Exploded Diagrams 2 Appendix LQ 2170 Service Manual A 24 Rev A ...
Page 171: ...Figure A 13 C S F Bin2 Exploded Diagrams LQ 2170 Service Manual Appendix Rev A A 25 ...
Page 172: ...Table A 15 Part No Reference Table Appendix LQ 2170 Service Manual A 26 Rev A ...
Page 173: ...Table A 15 Part No Reerence Table Continue LQ 2170 Service Manual Appendix Rev A A 27 ...
Page 174: ...Appendix LQ 2170 Service Manual A 28 Rev A ...
Page 175: ...EPSON Printed in Japan 95 12 05 S ...