Brother DCP-L8400CDN Service Manual page 227

(6) Open the Document scanner unit and pull out the First side CIS flat cable and Second
side CIS flat cable from the Flat core.
Document scanner unit
Flat core
First side CIS flat cable
Second side CIS flat cable
(7) Release all the wiring passes through the Hole of the Joint cover top.
(8) Change the angle of the Document scanner unit as shown in the figure to remove it from
the Main body.
Document scanner unit
Hole
Flat cable
Flat core
Fig. 3-57
Fig. 3-58
3-63
Joint cover top
Confidential