Oki Microline 520 Service Handbook page 242

RAP 08 Line Feed Problem
START
No line feed operation.
Make sure that the line feed cable is properly connected to the line feed motor and CN5 of the
main control board.
Power OFF the printer. Manually rotate the platen.
Does the platen rotate smoothly?
Yes Go to A
No Is the left platen gear broken?
Yes Replace the platen assembly.
End of procedure.
No Is the line feed idle gear broken?
Yes Replace the line feed motor assembly or the line feed idle gear.
End of procedure.
No Are the right platen gear, idle gear and/or change gear broken?
Yes Replace the respective assembly.
End of procedure.
No Set the change lever to the rear position.
Does the platen rotate smoothly?
Yes
End of procedure.
No
Go to A
Failure Analysis
Replace the tractor feed assembly.
Check the gears on the tractor feed assembly and platen assembly for
broken or missing teeth. Replace the defective assembly.
4 - 34 Microline 520/521 Service Handbook
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