Brother MFC-9420CN Service Manual page 125

5.1.14 Main PCB
(1) Disconnect the two connectors from the main PCB.
(2) Remove the four screws (A) from the main PCB.
Screws (A)
NCU harness ASSY connecto r
(3) Disconnect the connector of the main PCB from the engine controller board.
Main PCB
Screws (A)
Engine controller board
Fig. 5-56
Fig. 5-57
5 -3 6
Speaker harness connecto r
Main PCB
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