Brother MFC-J3520 Service Manual page 184

(12)Pull out the Second side CIS flat cable from the Hole of the Upper document chute.
Second side CIS flat cable
(13)Release the three Hooks and remove the Lower document chute from the
Document cover ASSY.
(14)Pull out the Second side CIS flat cable from the Hole of the Lower document chute.
Upper document chute
Hole
Second side CIS flat cable
13
Hole
Document cover ASSY
Fig. 3-63
Hook
Lower document chute
12
Fig. 3-64
3-64
Hook
Hook
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