Brother MFC-9420CN Service Manual page 103

(8) Remove the two pressure rollers from the pressure roller shaft.
(9) Open the ADF unit.
(10) Release the hook to remove the gear cover from the ADF unit.
ADF unit
Gear cover
Hook
Pressure roller shaft
Fig. 5-16
Gear cover
Fig. 5-17
5 -1 6
Pressure roller
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