Brother MFC9100C Service Manual page 111

1.34 Paper Width/Registration
Sensor PCB
(1) Remove two push nuts and take off the PCB film
(2) Remove the screw and take off the paper width/registration sensor PCB from the upper paper
chute.
Once removed, the components given in this
Caution Caution
subsection require the purge unit adjuster for
reassembly. Refer to Section 3, "ADJUSTMENT"
in this chapter.
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