Brother MFC9100C Service Manual page 201

2.4 Troubleshooting Procedures
[ 1 ] Control panel related
Trouble
(1) LCD shows nothing.
(2) Control panel inoperative.
[ 2 ] Telephone related
Trouble
(1) No phone call can be
made.
(2) Speed dialing or one-touch
dialing will not work.
(3) Speaker silent during on-
hook dialing.
(4) Dial does not switch
between tone and pulse.
• Panel-main harness
• Control panel PCB
• Power supply PCB
• Main PCB
• Panel-main harness
• Control panel PCB
• FPC key
• Main PCB
• FPC key
• Control panel PCB
• NCU PCB
• Main PCB
• Ordinary dialing function (other than the speed and one-touch
dialing)
If it works normally, check the main PCB; if not, refer to item
(1) above.
• Check speaker. If it works normally, refer to item (1) above.
• Main PCB
VI - 17
Check:
Check: