Epson FX 1170 - B/W Dot-matrix Printer, Service Manual

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REV.-A
Table 5-6. Repairing the Printer Mechanism (Continued)
Problem symptom
Cause
Checkpoint
Solution
Self test printing The carriage
The
common wires C h e c k t h e c o m m o n
Replace the FFC.
a b n o r m a l .
moves, but the self- in the printhead FFC wires in the
t e s t p r i n t i n g i s n o t
are disconnected, or printhead FFC.
executed.
there is no
continuity.
The printer does
The printhead is Measure the coil
Replace the
not print a
defective. resistance of the
(If any
particular dot.
The
pin is shorted, also
resistance should check the drivers
be approximately
on the main board.
16.5 ohms.
Check if the dot Replace the
wire is worn.
The printing is too The is Check if the tip of Replace the
light or the print defective. the dot wire is
density is not
worn.
uniform.
The platen gap is Set the LEVER, G. Adjust the gap as
not adjusted ADJUST to O and described in
properly. check the gap “Platen Gap
between the the
Adjustment” in
and the Chapter 4.
platen. The correct
gap is 0.36-0.40
mm.
Paper feeding The printer prints Foreign substances Visually check the Remove any
abnormal. but does not feed
are lodged in the paper path for any
foreign
paper properly. paper path. foreign substances.
substances.
The MOTOR
Check the gears for the
PF is not driving
damage or wear.
defective gear.
the gear correctly.
The MOTOR Measure the coil Replace the MOTOR
PF is defective.
resistance of the (If any
MOTOR coil is shorted, also
The resistance
check the drivers on
should be the main board.
approximately 63
ohms.
5-19