Troubleshooting Of The Control Panel - Brother DCP-9040CN Service Manual

8.

TROUBLESHOOTING OF THE CONTROL PANEL

Nothing is displayed on the LCD.
User Check
- Verify if the power switch is turned off.
- Pull out the power supply cord from the power outlet and leave it for 5 minutes or more.
Then, insert it to the power outlet again and turn on the power supply.
Step Possible cause
1 Connection
between main
PCB and control
panel PCB
Harness between
2
main PCB and
control panel PCB
Connection
3
between main
PCB and PS PCB
unit
4 Harness between
main PCB and PS
PCB unit
5 LCD
Control panel
6
PCB
PS PCB unit
7
8 Main PCB
Check
Are the main PCB and
control panel PCB
connected properly?
Is the harness damaged?
Are the main PCB and PS
PCB unit connected
properly?
Is the harness damaged?
Is the problem solved
after replacing the LCD?
Is the problem solved
after replacing the control
panel PCB?
Is the problem solved
after replacing the PS
PCB unit?
Is the problem solved
after replacing the main
PCB ASSY?
1-66
Remedy
Result
No Reconnect the connector
properly.
Yes
Replace the harness with
a normal one.
No
Reconnect the connector
properly.
Yes Replace the harness with
a normal one.
Yes Replace the LCD.
Yes
Replace the control panel
PCB.
Yes
Replace the PS PCB unit.
Replace the main PCB
Yes
ASSY.
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