Repair By Unit Replacement - Epson LQ-1170 Service Manual

5.2 REPAIR BY UNIT REPLACEMENT

For most problems, it is sufficient for you to determine the difficulty to the unit level. Refer to Table
5-3, identify what the problem is, then perform the checks according to the corresponding flowchart.
Symptom
Printer fails to operate when
power is on.
Carriage operation is abnor-
real.
Printing is faulty during self-
test, but carriage operation is
normal.
Paper feeding is abnormal.
Control panel operation is
abnormal.
Printing of data sent by the
host computer is faulty.
Table 5-3. Symptoms and Reference Pages
Carriage does not move.
Control panel indicator lamp does not light.
. Carriage moves away from home position at power
on.
but the printer then fails to enter the READY
No printing at all.
Fau Ity printing - some of the dots are not printed.
No paper is fed.
. Regular paper feed, but with variations in the separa-
I .
When the LF switch is activated, no paper is fed.
. Carriage operates normally at power on, and self-test
is executed correctly.
Print data from the computer, however, is not printed
correctly.
5-2
Problem See Page
5-3
5-4
mode.
5-5
5-9
5 - 1 2
I
5 - 1 3