Brother MFC-7450

1-54
Confidential
■ Speed dialing and One-touch dialing can't be used.
■ FAX can not be received.
Step Cause Check Result Remedy
1
Speed dialing
keys or one-
touch dialing
keys
Can a fax transmission
be made using the
numeric keys?
Ye s
Replace the main PCB
ASSY.
2
Dial mode
Setting
Can a dialing signal (PB
or DP) be heard
normally in each mode?
(Use telephone line
emulator if required.)
Ye s
Check the dialing mode
setting at customer's
again.
Check the telephone line
cord between machine and
socket.
3
Connection
between main
PCB and NCU
PCB
Are the main PCB and
NCU PCB connected
correctly?
No
Reconnect the connector.
4
Connection
between main
PCB and control
panel PCB
Are the main PCB and
control panel PCB
connected correctly?
No
Reconnect the connector.
5
Contact of rubber
keys
Is the problem solved
after replacing the
rubber keys?
No
Replace the rubber Keys.
6
NCU PCB Is the problem solved
after replacing the NCU
PCB ASSY?
Ye s
Replace the NCU PCB
ASSY.
7
Control panel
PCB
Is the problem solved
after replacing the
control panel PCB?
Ye s
Replace the control panel
PCB.
User Check
• Verify that the telephone cord is securely inserted.
Step Cause Check
Result Remedy
1
Receive mode
setting
Is the receive mode set
to automatic receive
mode?
No
Set the receive mode to
automatic receive mode.
2
NCU PCB Is the problem solved
after replacing the NCU
PCB ASSY?
Ye s
Replace the NCU PCB
ASSY.
3
Main PCB Is the problem solved
after replacing the main
PCB ASSY?
Ye s
Replace the main PCB
ASSY.