Brother MFC-7450

1-53
Confidential
11. Troubleshooting of fax functions
■ FAX can't be sent.
User Check
• Verify that the telephone cord is securely connected.
Step Cause Check
Result Remedy
1
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.
2
Connection
between main
PCB and NCU
PCB
Are the main PCB and
NCU PCB connected
correctly?
No
Reconnect the connector.
3
Connection
between main
PCB and control
panel PCB
Are the main PCB and
control panel PCB
connected correctly?
No
Reconnect the connector.
4
Contact of rubber
keys
Does the rubber keys
work correctly?
No
Replace the rubber Keys.
5
NCU PCB Is the problem solved
after replacing the NCU
PCB ASSY?
Ye s
Replace the NCU PCB
ASSY.
6
Control panel
PCB
Is the problem solved
after replacing the
control panel PCB?
Ye s
Replace the control panel
PCB.
7
Main PCB Is the problem solved
after replacing the main
PCB ASSY?
Ye s
Replace the main PCB
ASSY.