Epson DLQ-3000+ Service Manual page 155

DLQ-3000+
Condition



Symptom : Abnormal printing
Printhead Printhead control
control circuit circuit is
operates defective.
abnormally.
Printhead driver
circuit is
defective.
PG motor is not PG motor driver
functioning circuit is
properly. defective.
Note:


1. -No. shown in the diagram and corresponding dot No. are the same.
5-16
Table 5-13. Repair of C210 MAIN Board (continued)
Cause
If some particular dots are missing or
bad, check which head driver is
causing the problem, the driver for
print pulse A or B.

If any of the drivers is bad, see the
circuit diagram and replace the
corresponding drive transistors (
to

If both drivers are good, gate array


Figure 5-14. Head Drive Signal Waveform
Check pin 3 of 3-terminal regulator

!
&
defective.
Check pins 1,3,5,and 7 of
input signal waveform and pins 15/16,
13/14, 11/12 and 9/10 of
output signal waveform.

If no motor phase input signals is
input, gate array

If no drive waveforms is output,
is defective.
Check point
 $ $
, to ). (See Note 1.)
is defective.
for the correct output voltage
If it's correct, gate array


is defective.
Figure 5-15. PG Motor Drive waveform
Solution
Replace the
main control
board or
associated
component.

Replace the
%
main control


is
board or any
associated part.
$
for the
Replace the
main control
$
for board or any
associated
parts.
$
Rev. A