Pattern Cannot Be Selected - Brother NV-10A Service Manual

Failure Investigation for Electronic Parts Pattern cannot be selected
Is the connector of the operation PCB
assy. correctly connected to CN4 of the
main PCB assy.?
Is the shutter of the selecting shutter in
the concave portion of the photo
interrupter of the operation PCB assy.?

Pattern cannot be selected

Y
Y
Replace the main PCB assy.
N
Reconnect it correctly
Attach the operation PCB
N
assy. to the correct position
or
Replace the main PCB assy.
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