Oki ML420 Maintenance Manual

Also see for ML420 Series: Specification sheet User guide User guide Installation Installation

Contents

Oki ML420 Maintenance Manual Manual pdf 93 page image

Oki Data CONFIDENTIAL42113931TH Rev.1 93 /6. TROUBLESHOOTING AND REPAIR6.1 Items to Check Before Repair(1) Check the inspection items specified in the instruction manual.(2) Find out as many details of the trouble as possible from the customer.(3) Inspect in the conditions as close as possible to those at the time the trouble occurred.(4) Proceed with the repair as follows:Check the trouble status according to Table 6.1 for the details of the trouble. Then, locatethe trouble position according to the detailed flowchart.(5) Carry out a thorough test after the repair to check for correct functioning.6.2 Troubleshooting TableTable 6.1Status Trouble Contents TroubleshootingFlowchart No. Surmise of Trouble• Power is not supplied.• No spacing operation12Power Supply Unit,Main Control PCB,Space Motor, Carriage Cable,Printhead.• Homing does not end normally. 3Space Motor, Carriage Cable,Power Supply Unit, Main ControlPCB, Spacing MechanismTrouble uponpower on• Paper jam while paper insertion 4 Pressure Roller Mechanism, Pull UpRoller Cover.• Smearing/Missing dots 5 Printhead, Main Control PCB, SpaceMotor, Carriage Cable• Faint or dark print 6 Printhead, Ribbon Feed Assembly,Main Control PCB• Ribbon feed trouble 7 Ribbon Feed Assembly, SpaceMotor, Main Control PCB• Line feed trouble 8 LF Motor, Platen Assy, LFMechanism, Main Control PCB• Malfunction of switch onoperation panel 9 Operation Panel PCB,Main Control PCB• Data receiving failure 0Main Control PCB,(RS232C I/F Board),I/F Cable, Menu SettingTrouble duringprinting* Attention in exchange:When changed the Main control PCB, execute chapter 4 4-7 for setting the implementationprinter width (Wide / Narrow).