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1. Disassembly/Assembly Precautions
1-1. Precautions for disassembly and assembly
• Unplug the power cord from the electrical outlet before servicing the printer.
• Reassemble the unit in reverse order of disassembly unless otherwise instructed.
• If it is necessary to run the printer with its covers removed, use extreme care to avoid
catching your fingers or clothing in rotating parts such as gears, rollers, or motors.
• Never touch the terminals of electrical components or high-voltage components, such as
the power unit or the high-voltage unit.
• Be careful when working around the fusing unit because it will be hot long after the
printer is turned off. Wait until the fuser has cooled before disassembly.
• Turn off the printer before plugging or unplugging a power cord. Never plug or unplug a
power cord that is energized. When plugging or unplugging connectors, be sure to hold
the plug. Never pull on the cord or you may break the wires connecting the plug to the
power cord.
• Use only fuses of the specified rating.
• To ensure electrical conduction, attach the ground wire. In addition, be sure to use the
screws with toothed washers as instructed.
1-2. Parts that must not be touched
Do not remove, disassemble, or adjust any of the parts listed below:
• Print head unit (disassembly or adjustment)
• Components with mounting screws that are painted red.
1-3. Precautions for transporting or storing PWBs
Observe the following precautions when handling circuit boards.
• During transportation or storage, circuit boards must be placed in anti-static bags and
must not be unnecessarily removed. Do not wrap the circuit boards in plastic or paper
bags.
• Do not store or place circuit boards in a location exposed to direct sunlight.
• When it becomes necessary to remove a circuit board from the anti-static bag, do not
place it where it is easily be affected to static electricity, such as on carpet, plastic, or in
vinyl bags.
1-4. Precautions for replacing PWBs
• Generally, the PWB or the assembly should be replaced.
• When unplugging connectors from the circuit board, ensure the power is off.
• When removing a circuit board from its anti-static bag, or when replacing the circuit
board, hold the board by its edges, making sure not to touch pins of the ICs or the printed
pattern.
1-5. Precautions for inspecting PWBs
• Do not check ICs directly with a multimeter; use connectors on the circuit board.
• Never create a closed circuit across IC pins with a metal tool.
• When it is necessary to touch ICs and other electrical components on the circuit board,
be sure to first ground yourself.