Unit Level Troubleshooting - Epson FX 890 - B/W Dot-matrix Printer Service Manual

3.2 UNIT LEVEL TROUBLESHOOTING

You may be able to identify the defective unit just from the symptom displayed. The table below
provides the symptoms for a number of failures, so that you can easily identify the problem. Once
the problem has been identified, refer to the flowchart listed in the right-hand column of the table
below to determine the case of the problem.
Symptom
Printer fails to operate
when power is on.
Abnormal carriage
operation at power on.
Printing is faulty during
self-test, but carriage
operation is normal.
Abnormal paper
feeding
Abnormal control panel
operation
Data sent by the host
computer is printed
incorrectly
The repair procedure flowcharts use the following symbols:
Rev. B
Table 3-6. Symptoms and Problems
Carriage dose not move.
Control panel indicator LEDs do not light.
Carriage moves away from the home position at
power on.
Carriage returns to home position correctly, but the
printer then fails to enter the READY mode.
No printing at all.
Faulty printing
The printer prints but feeds paper incorrectly.
When the LF/FF switch is pressed, no paper is fed.
Carriage operates normally at power on, and self-test
is executed correctly, but data is not printed.
Data from the computer is printed incorrectly.
Figure 3-3. Symbols Used in the Flowcharts
FX-1180/FX-880 Service Manual
Problem
some dots are not printing.
Chapter 3 Troubleshooting
See Page
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