Brother MFC5890CN - Troubleshooting

4-33
Confidential
4.2.4 Troubleshooting Based on Problem Type
[ 1 ] Control panel and LCD problems
[ 2 ] FAX problems
[ 3 ] Communications problems
Problem Check:
(1) LCD shows nothing. • LCD and its flat cable
• Panel-main harness
• Control panel PCB
• Power supply PCB
•Main PCB
(2) Control panel inoperative. • Panel-main harness
• Control panel PCB
• Rubber keypads
•Main PCB
Problem Check:
(1) No faxes will be able to be sent. • Rubber keypads
• Control panel PCB
•Main PCB
•MJ PCB
(2) Speed dialing will not work. • Ordinary dialing function
If it works normally, check the main PCB; if not, refer to item
(1) above.
(3) Dial does not switch between
tone and pulse.
•Main PCB
(4) The ringer does not sound. • Speaker
•Main PCB
•MJ PCB
Problem Check:
(1) No tone is transmitted. • Main PCB
•MJ PCB