Troubleshooting For Control Panel Problems; Nothing Is Displayed On The Lcd; Nothing Is Displayed On The Led - Brother DCP-7080 Service Manual

4.6 Troubleshooting for Control Panel Problems

4.6.1 Nothing is displayed on the LCD

<User Check>
- Turn the power switch OFF and then ON again.
Step
Rubber key attachment failure
1
(For models without touch panel)
Connection failure of the panel
2
harness
Connection failure of the key PCB
3 flat cable
(For models with touch panel)
Connection failure of the LCD flat
4
cable
Connection failure of the LVPS
5
harness
Power cord failure
6
Rubber key failure
7
(For models without touch panel)
Panel PCB failure
8
Key PCB failure
9
(For models with touch panel)
LCD failure
10
(For models without touch panel)
Low-voltage power supply PCB
11
failure
Main PCB failure
12

4.6.2 Nothing is displayed on the LED

<User Check>
- Turn the power switch OFF and then ON again.
Step
Connection failure of the panel
1
harness
Panel PCB failure
2
Main PCB failure
3
Cause
Reattach the rubber key.
Reconnect the panel harness.
Reconnect the key PCB flat cable.
Reconnect the LCD flat cable.
Reconnect the LVPS harness.
Replace the power cord.
Replace the panel unit.
Replace the panel PCB ASSY.
Replace the panel unit.
Replace the LCD.
Replace the low-voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
Cause
Reconnect the panel harness.
Replace the panel PCB ASSY.
Replace the main PCB ASSY.
2-80
Remedy
Remedy
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