Brother MFC-9420CN Service Manual page 143

(3) Remove the setscrew (TS3x12, 4 pieces) of the laser ASSY PU.
(4) Disconnect the connector connecting to the laser ASSY PU.
(5) Remove the laser ASSY PU from the frame.
CAUTION:
• Laser beam of the class IIIB is scanned in the laser ASSY PU. Do not attempt to
disassemble the laser ASSY PU because it is dangerous.
• The laser ASSY PU for maintenance is replaceable by the unit. No internal adjustment is
required for the laser ASSY PU.
• Test drive and confirmation of the drive must be done only after installing the cover to
prevent the laser beam from being transmitted out of the machine.
Laser ASSY PU
TS3x12
Frame
Fig. 5-90
5-56 Confidential