Brother NV4000D Service Manual page 367

Failure Investigation for Electronic Parts Error is displayed
The error message "F05" or "F06"
is displayed on the screen.
Is the NP PCB assembly (D6)
correctly connected to the main
PCB assembly (CN15)?
When the NP PCB assembly (D6)
is replaced with a new one, does it
work correctly?
Y
Y
Replace the NP PCB assembly.
Correctly connect the NP
N
PCB assembly (D6) to the
main PCB assembly (CN15).
N
Replace main PCB assy.
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