Brother International DCP-1400 Service Manual - Page 157

2.4 Troubleshooting Procedures [ 1 ] Control panel related Trouble (1) LCD shows nothing. (2) Control panel inoperative. Check: • Panel harness between the control panel PCB and relay PCB • Main-relay (panel) harness between the relay PCB and main PCB • Control panel PCB • Low-voltage power supply PCB • Main PCB • LCD • Panel harness between the control panel PCB and relay PCB • Main-relay (panel) harness between the relay PCB and main PCB • Control panel PCB • FPC key • Main PCB [ 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. (5) Telephone does not ring. • FPC key • Control panel PCB • NCU PCB • Main PCB Check: • 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. • Ordinary dialing function (other than the on-hook dialing with the hook key) If it works normally, proceed to the following checks; if not, refer to item (1) above. • Main PCB • Speaker • NCU PCB • Main PCB VI - 19