Telephone related

2.4Troubleshooting Procedures [ 1 ] Control panel related

	Trouble		Check:

(1)	LCD shows nothing.	•	Panel-main harness between the main PCB and the
			control panel PCB
		•	Control panel PCB
		•	Low-voltage power supply PCB
		•	Main PCB
		•	LCD

(2)	Control panel inoperative.	•	Panel-main harness between the main PCB and the
			control panel PCB
		•	Control panel PCB
		•	FPC key
		•	Main PCB

[ 2 ]	Telephone related

	Trouble		Check:

(1)	No phone call can be made.	•	FPC key
		•	Control panel PCB
		•	NCU PCB
		•	Main PCB

(2)	Speed dialing or one-touch	•	Ordinary dialing function (other than the speed and
	dialing will not work.		one-touch dialing)
			If it works normally, check the main PCB; if not, refer
			to item (1) above.

(3)	Speaker silent during on-hook	•	Ordinary dialing function (other than the on-hook
	dialing.		dialing with the hook key)
			If it works normally, proceed to the following checks; if
			not, refer to item (1) above.

(4)	Dial does not switch between	•	Main PCB
	tone and pulse.

(5)	Telephone does not ring.	•	Speaker
		•	NCU PCB
		•	Main PCB

VI - 16