Brother International MFC 8890DW Service Manual - Page 142

Speed dialing and One-touch dialing can't be used., FAX can't be received., Replace the NCU PCB

Page 142 highlights

■ Speed dialing and One-touch dialing can't be used. Step 1 2 3 4 5 6 7 8 Possible cause Check Result Remedy Speed dialing keys or onetouch dialing keys Can a fax transmission be made using the numeric keys? Replace the main PCB Yes ASSY. Dialing mode Setting Does a dialing signal (PB or DP) come out normally in each mode? (Use telephone line emulator.) Check the dialing mode setting at customer's Yes again. Check the telephone line cord between machine and socket. Connection between main PCB and NCU PCB Are the main PCB and NCU PCB connected properly? Reconnect the connector No properly. Harness between main PCB and NCU PCB Is the harness damaged? Replace the harness with a Yes normal one. Connection between main PCB and control panel PCB Are the main PCB and control panel PCB connected properly? Reconnect the connector No properly. Harness between main PCB and control panel PCB Is the harness damaged? Replace the harness with a Yes normal one. Contact of rubber Is the problem solved key after replacing the rubber key? Replace the rubber Key. Yes NCU PCB Is the problem solved after replacing the NCU PCB ASSY? Replace the NCU PCB Yes ASSY. Control panel 9 PCB Is the problem solved after replacing the control panel PCB? Replace the control panel Yes PCB. ■ FAX can't be received. - Verify that the telephone cord is securely inserted into the right socket. Step 1 2 3 Possible cause Receive mode setting NCU PCB Main PCB Check Is the receive mode set to automatic receive mode? Is the problem solved after replacing the NCU PCB ASSY? Is the problem solved after replacing the main PCB ASSY? Result Remedy Set the receive mode to No automatic receive mode. Replace the NCU PCB Yes ASSY. Replace the main PCB Yes ASSY. 3-70 Confidential

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3-70
Confidential
Speed dialing and One-touch dialing can't be used.
FAX can't be received.
Step
Possible cause
Check
Result
Remedy
1
Speed dialing
keys or one-
touch dialing
keys
Can a fax transmission
be made using the
numeric keys?
Yes
Replace the main PCB
ASSY.
2
Dialing mode
Setting
Does a dialing signal
(PB or DP) come out
normally in each mode?
(Use telephone line
emulator.)
Yes
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
properly?
No
Reconnect the connector
properly.
4
Harness
between main
PCB and NCU
PCB
Is the harness
damaged?
Yes
Replace the harness with a
normal one.
5
Connection
between main
PCB and control
panel PCB
Are the main PCB and
control panel PCB
connected properly?
No
Reconnect the connector
properly.
6
Harness
between main
PCB and control
panel PCB
Is the harness
damaged?
Yes
Replace the harness with a
normal one.
7
Contact of rubber
key
Is the problem solved
after replacing the
rubber key?
Yes
Replace the rubber Key.
8
NCU PCB
Is the problem solved
after replacing the NCU
PCB ASSY?
Yes
Replace the NCU PCB
ASSY.
9
Control panel
PCB
Is the problem solved
after replacing the
control panel PCB?
Yes
Replace the control panel
PCB.
<User Check>
-
Verify that the telephone cord is securely inserted into the right socket.
Step
Possible 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?
Yes
Replace the NCU PCB
ASSY.
3
Main PCB
Is the problem solved
after replacing the main
PCB ASSY?
Yes
Replace the main PCB
ASSY.