Brother MFC4820C Service Manual page 5

6.1 DISASSEMBLY/REASSEMBLY
Safety Precautions
To prevent the creation of secondary problems through mishandling, observe the following
precautions for maintenance work.
(1) Unplug the power cord from the power outlet before replacing parts or units. When accessing
to the power-related sections, be sure to unplug the power cord from the power outlet.
(2) Be careful not to lose screws, washers or any 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) Before handling the PCBs, touch a metal portion of the machine to discharge the static
electricity in your body; otherwise, the electronic parts may be damaged.
(5) When transporting PCBs, be sure to wrap them in conductive sheets such as aluminum foil.
(6) If any of the self-tapping (Taptite) screws are removed, be sure to reinsert them correctly.
(7) Tighten screws to the torque values listed on the next page.
(8) When connecting or disconnecting cables, hold the connector bodies not the cables themselves.
If the connector has a lock, always slide the lock to unlock the connector.
(9) After repairs, check not only the repaired portion but also that the connectors and other related
portions function properly before performing any operational checks.
(10) The print head unit will start head locking operation five seconds after the printing is finished.
Head locking operation takes from 5 to 10 seconds. NEVER unplug the power cord before the
print head unit completes the head locking operation; doing so will render the print head unit
unusable, and therefore require replacement.
When you receive the machine from the user or when you pack it to send it back to the user,
check the head locking state.
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