Epson LX-300 Service Manual page 60

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