Brother DCP-L8400CDN Service Manual page 262

(10) Disconnect the Connector from the ADF cover/document detection sensor PCB ASSY.
ADF cover/document detection
sensor PCB ASSY
(11) Lift the film. (Only when the Film is inserted)
(12) Push and open the Rib and remove the Second side document scanning position sensor
PCB ASSY from the Lower ADF chute.
Film
Lower ADF chute
First side document scanning
position sensor PCB ASSY
Fig. 3-117
Rib
Second side document
scanning position sensor
PCB ASSY
11
Fig. 3-118
3-98
Connector
12b
12a
12c
Second side document
scanning position sensor
PCB ASSY
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