Table 5-7. Repairing the C186 MAIN Board Assembly
Problem
Cause
Checkpoint
Solution
Paper feed is
abnormal.
IC1 is defective.
or
IC2 is defective.
or
IC11 or IC14 is
defective.
Check input signal waveform at 8 pin
on the both IC11 and IC14.
Check output signal waveform at 1 and
15pin on the both IC11 and IC14.(CH1)
If the input signal
is not correct,
replace IC1 or
IC2. ( or replace
the main borad)
If the input signal
is correct and the
output signal is
not correct,
replace the IC11.
No data is
printed.
IC1 is defective.
Check the output signal waveform at pin
15 of IC1.
If this signal is
not output,
replace IC1.
( or replace the
main board)
A particular
dot fails to
print.
IC2 is defective.
or
One of the head drive
transistors is defective
(Q1 ~ Q24).
Check the voltage waveform (CH1) at
pin 69 and pins 76 ~ 89, pins 91~ 99 of
IC2.
Check the voltage waveform (CH2) for
each transistor.
If the head drive
signal is not
output, replace
IC2.( or replace
the main board)
If the head drive
signal is output
from the head
drive transistors,
replace the head
drive transistor.
LQ-2070 Service Manual
Troubleshooting
Rev.A
5-15
Содержание 2070 - LQ B/W Dot-matrix Printer
Страница 1: ...EPSON TERMINAL PRINTER LQ 2070 SERVICE MANUAL EPSON 4006244 ...
Страница 5: ...REVISION SHEET Revision Issued Date Revision Page Rev A April 8 1996 1st issued ...
Страница 11: ...Product Description LQ 2070 Service Manual Figure 1 1 Exterior View of the LQ 2070 1 2 Rev A ...
Страница 55: ...LQ 2070 Service Manual Operating Principles Rev A 2 7 ...
Страница 58: ...Operation Principles LQ 2070 Servcie Manual 2 10 Rev A ...
Страница 63: ...Down LQ 2070 Service Manual Operating Principles Rev A 2 15 ...
Страница 112: ...Disassembly and Assembly LQ 2070 Service Manual 3 34 Rev A ...
Страница 146: ...Maintenance LQ 2070 Service Manual 6 4 Rev A ...
Страница 165: ...EPSON ...