Brother MFC-9420CN Service Manual page 122

(8) Remove the LCD harness from the panel PCB.
Lock
Panel unit
Panel PCB
LCD harness
Fig. 5-51
(9) Remove the rubber key.
NOTE: When re-assembling the rubber key, make sure that the key works correctly.
Rubber key
Bosses
Panel uni t
Bosses
Bosses
Bosses
Fig. 5-52
5 -3 3
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