Brother MFC-9420CN Service Manual page 114

(31) Release the two hooks "A" on the lower document chute to remove the ADF sensor PCB
ASSY.
Hooks " A "
(32) Turn the lower document chute upside down.
(33) Release the pins and remove the document hold.
(34) Remove the document spring from the lower document chute.
Document spring
1
Pin
Lower document chute
A DF sensor PCB ASS Y
1
1
2
Fig. 5-35
Hooks
3
2
Fig. 5-36
5 -2 5
Lower document chute
3
Hooks
Document hold
Hook
1
Pin
Confidential