Unit Level Troubleshooting - Epson LX-300 Service Manual

Troubleshooting

UNIT LEVEL TROUBLESHOOTING

5.2
Y may be able to identify the defective unit just from the symptom displayed. The table below
OU
provides the symptoms for a number of failures, so that
the m-oblem has been identified, refer to the flowchart listed in the right-hand cAmn of the table
Table 5-7. Symptoms and Problems
S y m p t o m
. Carriage does not move.
Printer fails to operate
when the power is on. . Control panel indicator LEDs do not light.
Abnormal carnage
The carriage returns to home position correctly, but the
operation.
Printing is faulty
during self-test, but No printing at all.
carriage operation is
Faulty printing — some of the dot are not printing.
normal.
Abnormal paper feed. The printer prints but paper feeds incorrectly.
Abnormal control
When the LF/FF button is pressed, no paper is fed.
panel operation.
Data sent by the host Carriage operates normally at power up, and self-test
computer is printed
incorrectly. Data from the computer is printed incorrectly.
I
5-4
Problem
printer then fails to enter the READY mode.
is executed correctly, but data .k not printed.
Start
Processing
Forwarding to
another item
Decision
Figure 5-3. Flowchart Symbols
LX-300 Swvfce Manual
YOU
Branching
Return to the
of the
Start item
N
END
, -~--:,
See Page
5-5
5-6
5-7
5-8
5-9
5-1o
.