EPSON FX-2180 Service Manual Chapter 3 Troubleshooting
3-11
Table 3-7. Repairing the Main Board Assembly (Continued)
Problem Cause Checkpoint Solution
A particular
dot does not
print.
IC1 is
defective, or
one of the
print head
drive
transistors
(Q2 − Q19) is
defective.
• Check the input signal
waveform (CH 1) at the
base of each transistor.
• Check the output signal
waveform (CH 2) at the
collector for each transistor.
CH 1
CH 2
Figure 3-18.
Waveform 11
• If an input
signal is not
correct, replace
the main board.
• If an output
signal is not
correct, replace
the transistor or
the main board.
3.6 Repairing the Printer Mechanism
The table below describes how to repair the printer mechanism. It lists
various printer mechanism problems and symptoms, and provides likely
causes, checkpoints, and solutions. The checkpoint column lists what to
check and indicates how the printer mechanism works when it is operating
properly. The solution column tells you how to repair the printer
mechanism.
For replacement and adjustment instructions, see Chapter 4,
“Disassembly and Assembly,” and Chapter 5, “Adjustment.” If the same
symptom recurs after you repair the printer mechanism, select another
probable cause and repair the printer mechanism again.
Table 3-8. Repairing the Printer Mechanism
Problem Symptom Cause Checkpoint Solution
Carriage
operation is
abnormal.
When you turn on
the printer, the CR
motor does not
rotate at all.
The CR
motor is
defective.
Measure the
CR motor’s coil
resistance. It
should be
approx. 2.7 Ω.
(See Table
3-3.)
Replace
the CR
motor.
When you turn on
the printer, the CR
motor does not
rotate at all and
the control panel
LEDs flash.
CN11 is not
properly
connected to
the main
board.
Check the
connection.
Connect
CN11.
When you turn on
the printer, the CR
motor rotates but
the carriage does
not move.
The timing
belt has
come off the
pinion gear of
the CR
motor.
Check the
timing belt.
Replace
the timing
belt.
The carriage
moves slightly and
then stops.
The platen
gap is too
narrow.
Move the
carriage by
hand to check if
it moves
smoothly.
Check the
platen gap
and adjust
it if it is too
small. See
Chapter 5.
