Oki ML420 Maintenance Manual page 109

Ribbon feed trouble
7
Remove the ribbon cartridge.
Move carriage to left and right.
Does the ribbon drive shaft rotate?
No Yes
Change Ribbon cartridge.
Remove Ribbon feed mechanism.
Move carriage to left and right.
Does the ribbon drive shaft rotate?
No Yes
Replace Ribbon feed mechanism.
Replace Space motor assy.
42113901TH01 Rev.3
Oki Data CONFIDENTIAL
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