Brother MFC-3420C - Manual (Page 67)

4 - 9 GETTING STARTED
On/Off Setting
You can customize machine’s On/Off key. The default setting is Off .
Your MFC will not work when it is switched Off, but it will purge the
ink head periodically. If you turn this setting to
On , you can receive
faxes or calls even when the MFC is switched Off.
1
Press Menu/Set , 1 , 6 .
2
Press or to select On (or
Off ).
3
Press Menu/Set .
4
Press Stop/Exit .
6.On/Off Setting