Brother MFC-8912DW - 4.10 Troubleshooting for PCB Problems

2-91
Confidential
4.10 Troubleshooting for PCB Problems
4.10.1 Main PCB failure
4.10.2 High-voltage power supply PCB failure
4.10.3 Low-voltage power supply PCB failure
<User Check>
- Turn the power switch OFF and then ON again.
- Install the latest firmware.
Step Cause Remedy
1 Main PCB failure Replace the main PCB ASSY.
Step Cause Remedy
1
Connection failure of the high-
voltage power supply PCB harness
Check the harness connection between the
high-voltage power supply PCB and the
main PCB ASSY, and reconnect it if
necessary.
2
Contact failure of electrode
terminals of the high-voltage power
supply PCB
Clean the electrode terminals of the high-
voltage power supply PCB.
3
High-voltage power supply PCB
failure
Replace the high-voltage power supply PCB
ASSY.
4
Low-voltage power supply PCB
failure
Replace the low-voltage power supply PCB
ASSY.
5 Main PCB failure Replace the main PCB ASSY.
Step Cause Remedy
1
Connection failure of the low-
voltage power supply PCB harness
Check the connection of the low-voltage
power supply PCB harness, and reconnect
it if necessary.
2
Low-voltage power supply PCB
failure
Replace the low-voltage power supply PCB
ASSY, and reset the irregular power supply
detection counter.
3 Main PCB failure Replace the main PCB ASSY.
CAUTION:
• The irregular power supply detection error (error code EF00) occurs when there is a
large distortion in the power supply voltage supplied to the machine. In this case, if the
same power supply is used, the same error may occur even when the low-voltage
power supply PCB ASSY is replaced. Ask the user to review the installation
environment.