Service manual

Troubleshooting
EPSON FX-880/FX-1180 Service Manual
5-21
Repairing the Printer Mechanism
This section provides instructions for repairing the printer mechanism. It describes various problems,
symptoms, likely causes, checkpoints, and solutions. The checkpoint column shows items to be checked,
including proper values to be set for each component of the printer mechanism. For disassembly
instructions, see Chapter 3. For adjustment instructions, see Chapter 4.
Table 5-13. Repairing the Printer Mechanism
Symptom Condition Possible
Cause
Checkpoint Solution
CR
operation is
abnormal.
Carriage does
not move even
after power is
turned on.
A foreign object
is blocking the
mechanism.
Manually move the timing
belt to check that the motor
rotates normally.
Remove any
foreign objects.
The platen gap
may be badly
adjusted.
Check for the proper
adjustment. (See Chapter 4.)
Adjust the platen
gap.
CR motor is
defective
❏
Measure the coil resistance
of the motor. (It should be
16 Ω ± 10%. See Table
5-3.)
❏
If there’s a short circuit in
the motor, see if there’s
also a short-circuit in the
driver circuit (IC8) on the
main board.
Replace the CR
motor or main
board.
The CR motor
rotates, but the
carriage does
not move.
The pulley drive
is defective.
Check to see if the pulley is
broken or worn out.
Replace the
pulley drive.
The timing belt
is defective.
❏
Check whether the timing
belt is installed correctly on
the carriage.
❏
Make sure the timing belt is
not broken or worn out.
Replace or
reinstall the
timing belt.
The carriage
moves a little to
the left, then
stops.
The carriage
does not move
smoothly.
Check that the carriage
moves smoothly when
moved by hand.
Clean and
lubricate the CR
guide shaft and
frame, or replace
the CR motor.
The carriage
stops after
moving to the
right or left
margins.
The HP sensor
is defective.
Use the multimeter to check
the HP sensor. (See Table
5-8.)
Replace the HP
sensor.