Service manual

EPSON LX-300+ Revision A
Troubleshooting Troubleshooting 60
Table 3-6. Self Test Print is Abnormal.
Cause Check Point Y/N Solution
Any of CN3 to
CN12 is not
connected to the
main board
properly.
Are all
connectors
connected
properly?
NO Connect them properly.
Printhead driver is
defective.
- - Replace the main board.
Bi-d is not correct.
Are rows aligned
properly when bi-
directional
printing is
proceeded?
NO Adjust Bi-D.
Printhead is
defective.
Is there any dot
missing?
YES Replace the printhead.
Head FFC is not
connected
properly or broken.
- YES Replace the head FFC.
Platen gap is not
correct.
Is printing too
light / weak?
YES Adjust the platen gap.
Is there any dirt
on printed
documents?
YES Adjust the platen gap.
Ribbon mask is
defective.
Is there any dirt
on printed
documents?
YES Replace the ribbon mask.
Ribbon
mechanism is
defective.
Is ribbon
advanced
properly?
NO
Replace the ribbon mechanism
parts.
Printer mechanism
is defective.
- -
Replace the printer
mechanism.
Table 3-7. Paper Feed is Abnormal.
Cause Check Point Y/N Solution
RPE detector or
BPE detector is
defective or not
connected
properly.
Check the
sensors. Is there
any abnormality?
NO Replace the sensor.
YES
Check the connection to the
main board.
Paper switching
mechanism is
defective.
Switch the
release lever. Is
the paper loading
direction
switched?
NO
Replace the printer
mechanism or check the
connection.
Can the release
lever be
switched?
NO
Replace the release sensor or
check the connection.
Printer mechanism
paper loading
mechanism is
defective.
When the power
is off, can the
printer feed
paper by rotating
the platen knob
manually?
NO
Replace the printer
mechanism or paper loading
mechanism parts.
PF motor is
defective.
Is PF motor
normal?
NO Replace the PF motor.
PF motor driver is
defective.
- - Replace the main board.
Table 3-8. Control Panel and Switches Do Not Operate.
Cause Check Point Y/N Solution
Switch is defective.
Is conductivity of
the switch is OK?
NO Replace the control panel.
Connect the
control panel
harness.
Control panel
harness is
connected
properly?
NO Connect it properly.
Control panel
board is defective
or the harness is
defective.
- - Replace the control panel.