Control Panel Problems; No Display On Lcd; No Display On Led; The Control Panel Does Not Work - Brother MFC-J3520 Service Manual

4.6

Control Panel Problems

4.6.1 No display on LCD

Step
1 LCD PCB harness connection
failure
2 LCD harness connection
failure
3 LCD unit defective
4 LCD PCB ASSY defective
5 Power supply PCB and
power cord defective
6 Main PCB defective

4.6.2 No display on LED

Step
1 LCD PCB harness connection
failure
2 Panel PCB harness
connection failure
3 LCD PCB ASSY defective
4 Panel PCB defective
5 Power supply PCB and
power cord defective
6 Main PCB defective

4.6.3 The control panel does not work

Step
1 Panel PCB harness
connection failure
2 Panel PCB defective
3 Power supply PCB defective
4 Main PCB defective

4.6.4 Touch panel inoperative

Step
1 LCD PCB harness connection
failure
2 Touch panel harness
connection failure
3 LCD PCB ASSY defective
4 Touch panel ASSY defective
5 Power supply PCB defective
6 Main PCB defective
Cause
Reconnect the LCD PCB harness.
Reconnect the LCD harness.
Replace the LCD unit.
Replace the LCD PCB ASSY.
Replace the power supply PCB ASSY.
Replace the main PCB ASSY.
Cause
Reconnect the LCD PCB harness.
Reconnect the panel PCB harness.
Replace the LCD PCB ASSY.
Replace the panel ASSY.
Replace the power supply PCB ASSY.
Replace the main PCB ASSY.
Cause
Reconnect the panel PCB harness.
Replace the panel ASSY.
Replace the power supply PCB ASSY.
Replace the main PCB ASSY.
Cause
Reconnect the LCD PCB harness.
Reconnect the touch panel harness.
Replace the LCD PCB ASSY.
Replace the touch panel ASSY.
Replace the power supply PCB ASSY.
Replace the main PCB ASSY.
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Solution
Solution
Solution
Solution
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