Troubleshooting For Control Panel Problems; Nothing Is Displayed On The Lcd; Control Panel Is Inoperable - Brother DCP-8110DN Service Manual

4.6

Troubleshooting for Control Panel Problems

4.6.1 Nothing is displayed on the LCD

Step
1 AC cord failure
Connection failure of the panel
2
harness
Connection failure of the backlight
3
harness
Connection failure of the LCD
4
harness
5 LCD failure
6 LCD flat cable or LCD ASSY failure Replace the LCD ASSY.
7 Backlight ASSY failure
8 Panel PCB failure
9 Touch panel PCB failure
Low-voltage power supply PCB
10
failure
11 Main PCB failure

4.6.2 Control panel is inoperable

<User Check>
- Check that the function lock is not set.
Step
1 Panel unit attachment failure
Connection failure of the panel PCB
2
harness
Connection failure of the touch
3
panel PCB harness
Connection failure of the touch
4
panel harness
5 Rubber key failure
6 Panel PCB failure
7 Touch panel PCB failure
8 Touch panel ASSY failure
Low-voltage power supply PCB
9
failure
10 Main PCB failure
Cause
Replace the AC cord.
Check the connection of the panel harness,
and reconnect it if necessary.
Check the connection of the backlight
harness, and reconnect it if necessary.
Check the connection of the LCD harness,
and reconnect it if necessary.
Replace the LCD.
Replace the backlight ASSY.
Replace the panel PCB ASSY.
Replace the touch panel PCB ASSY.
Replace the low-voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
Cause
Reattach the panel unit.
Check the connection of the panel PCB
harness, and reconnect it if necessary.
Check the connection of the touch panel
PCB harness, and reconnect it if necessary.
Check the connection of the touch panel
harness, and reconnect it if necessary.
Replace the rubber key R, L or C.
Replace the panel PCB ASSY.
Replace the touch panel PCB ASSY.
Replace the touch panel ASSY.
Replace the low-voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
2-87
Remedy
Remedy
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