Brother Facsimile Equipment MFC7420 - Manual (Page 72)

Confidential 5 -1
5.1 DISASSEMBLY/REASSEMBLY
Safety Precautions
To prevent the creation of secondary problems by mishandling, observe the following
precautions during maintenance work.
(1) Before starting disassembly/reassembly jobs, unplug the power cord and telephone line.
In particular, when having access to the power supply inside the machine, make sure that
the power cord is unplugged from the electrical outlet; when having access to the main
PCB or NCU PCB, make sure that both the power cord and telephone line are unplugged
from the machine.
(2) Be careful not to lose screws, washers, or other parts removed for parts replacement.
(3) When using soldering irons and other heat-generating tools, take care not to damage the
resin parts such as wires, PCBs, and covers.
(4) Static electricity charged in your body may damage electronic parts.
Before handling the PCBs, touch a metal portion of the machine to discharge static
electricity charged in your body. When transporting PCBs, be sure to wrap them in
conductive sheets such as aluminum foil.
(5) Be sure to reinsert self-tapping screws correctly, if removed.
(6) Tighten screws to the torque values listed on the next page.
(7) When connecting or disconnecting cable connectors, hold the connector bodies not the
wires. If the connector has a lock, always slide the connector lock to unlock it.
(8) Before reassembly, apply the specified lubricant to the specified points.
(Refer to Section 5.2 in this chapter.)
(9) After repairs, check not only the repaired portion but also that the connectors and other
related portions function properly before operation checks.
(10) After you use the machine, some internal parts are extremely HOT! To prevent injuries,
be careful not to put your fingers in the areas shown in the illustration.