Brother MFC990CW Service Manual page 210

Document rear sensor PCB
(15) Turn the ADF unit right side up.
(16) Lightly push down the two lock arms and take out the document rear sensor PCB. Then
disconnect the document rear sensor harness from the PCB and release it from the cable
guides provided on the ADF unit.
Document rear sensor PCB
Document rear sensor
harness
Document feed roller 1
Document rear sensor harness
Assembling Note: Route the document rear sensor harness through the cable guides
provided on the ADF unit as shown below.
Document rear sensor harness
Document rear sensor PCB
Document feed roller 2
Document feed roller 1
ADF unit
Document feed roller 1
ADF unit
(Left)
Top view
6-26
Document feed roller 2
Document rear sensor PCB
Lock arms
Document feed roller 2
Cable guides
ADF drive unit
(Rear)
ADF unit
(6_23)
(6_31)
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