Service manual

SERVICE MANUAL MASTER FILE
ENGLISH
Rev. A (1997/05/07)
3-4
.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.
Table 3-5. Symptoms and Problems
Symptom Problem See Page
Printer fails to operate
when power is on.
Carriage dose not move.
Control panel indicator LEDs do not light.
3-5
Abnormal carriage
operation at power on.
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.
3-6
Printing is faulty during
self-test, but carriage
operation is normal.
No printing at all.
Faulty printing

some of the dots are not printing.
3-7
Abnormal paper
feeding
The printer prints but feeds paper Incorrectly.
3-8
Abnormal control panel
operation
When the LF/FF switch is pressed, no paper is fed.
3-9
Data sent by the host
computer is printed
incorrectly
Carriage operates normally at power on, and self-
test is executed correctly, but data is not printed.
Data from the computer is printed incorrectly.
3-10
The repair procedure flowcharts use the following symbols:
START
END
Start
Preocessing
Forwarding to
another items
Decision
Return to the
Start of the item
END
Branching
Figure 3-3. Symbols Used in the Flowcharts