VI - 16
2.4 Troubleshooting Procedures
[ 1 ] Control panel related
Trouble Check:
(1) LCD shows nothing. lPanel-main harness between the main PCB and the
control panel PCB
lControl panel PCB
lLow-voltage power supply PCB
lMain PCB
lLCD
(2) Control panel inoperative. lPanel-main harness between the main PCB and the
control panel PCB
lControl panel PCB
lFPC key
lMain PCB
[ 2 ] Telephone related
Trouble Check:
(1) No phone call can be made. lFPC key
lControl panel PCB
lNCU PCB
lMain PCB
(2) Speed dialing or one-touch
dialing will not work.
lOrdinary 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.
(3) Speaker silent during on-hook
dialing.
lOrdinary 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.
(4) Dial does not switch between
tone and pulse.
lMain PCB
(5) Telephone does not ring. lSpeaker
lNCU PCB
lMain PCB