%3.1.03 Maintenance Precautions3.1.03 Maintenance Precautions1. Do not disassemble the unit if it is operating normally.2. Before starting disassembly and assembly, always turn the AC power switch OFF and pull outthe AC plug.3. Detach the interface cable, if installed.4. Do not remove parts unnecessarily. Try to keep disassembly to a minimum.5. Use the recommended maintenance tools.6. When disassembling, follow the listed sequence. Failure to follow the correct sequence mayresult in damaged parts.7. Since screws, collars and other small parts are easily lost, they should be temporarily attached tothe original positions.8. When handling circuit boards use extreme care. Integrated circuits (microprocessors, ROM, andRAM) can be destroyed by static electricity.9. Do not place printed circuit boards directly on conductive surfaces.10. Follow the recommended procedures when replacing assemblies and units.11. Perform the printhead gap adjustment procedure (Refer to Section 3.3 of this ServiceHandbook) when the any of the following occur.Print Quality is darker on one side of the document.Parts are replacedPrinthead (3.2.02)Space Motor Assembly (3.2.11)Space Rack (3.2.13)Guide Rail (3.2.15)Platen Assembly (3.2.19)Carriage Shaft (3.2.25)ML520/521 ( 96-02-04 )
