Service manual

REPAIR
Troubleshooting
SERVICE MANUAL
3-8
Points to Check Probable Cause Corrective Action Repair
Does the signal level at pin 1 of
CN13 remain HIGH when the
carriage index switch is closed?
Broken wire in the
carriage index switch
assembly
Replace the carriage
index switch assembly
(after confirming
discontinuity).
Is the carriage index switch
connected to CN13?
Incorrect connection Reconnect.
Problem:
Keys malfunction (do not insert characters or insert wrong characters)
Points to Check Probable Cause Corrective Action Repair
Is the key top and the key actuator
correctly mounted?
Faulty keyboard
assembly
Replace the
keyboard.
Is the keyboard FPC securely
connected to Main PCB CN12?
Keyboard PCB not
connected properly.
Reconnect.
When a bad key is pressed, does
the matrix row in which the pressed
key is connected go LOW in
synchronization with the output
timing of output drive #8?
If YES, faulty Main
PCB.
If NO, faulty keyboard.
Replace the Main
PCB.
Replace the
keyboard.
Is solder present at the correct
country specification change-over
solder point?
Incorrect or faulty
solder point for
specified country
(language)
Verify and correct
solder point.
Problem:
[Abnormal Printing]
• Voids in characters • Light print • Prints off the page
• Prints satellites • Carrier moves, but does not print
• Print head dries out prematurely • Vertical alignment off
• Ink smearing • Vertical streaks on paper
• Print lines crowded • Gaps or overlapped areas in print
• Will not print in color • Colors will not print correctly.
Points to Check Probable Cause Corrective Action Repair
(1) Print Cartridge:
Is the ink cartridge good, and is
it properly installed?
Cartridge empty, dried
out, or not locked in
and aligned with
contacts in carriage.
Replace with a new
cartridge, and/or
properly install the ink
cartridge.
Replace the ink
cartridge
and/or the
printer flat
cable.
After executing the purge (auto
printhead cleaning) function from
the keyboard
(CODE+SHIFT+INK CHG), are
there still printing problems?
Dirty or clogged ink jet
nozzles
Replace the ink
cartridge and run the
Self-Print test, and/or
replace the printer flat
cable.
(2) Printhead Carriage Assembly:
Is the flat cable firmly connected
in the Main PCB?
Loose or worn
printhead flat cable.
Reconnect loose flat
cable or replace it.
Replace flat
cable.
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