NEC SL1100 User Manual page 13

Things to Check if you Experience Problems
There are a few things that we ask customers to try before calling us as it
can save both us and the customer time as well as helping us to pinpoint
the problem more easily. It also helps us to know if we will need to bring
any replacement items, such as handsets or even a new system. This
process can be speeded up if you, the customer, is willing to help us
narrow down the possibilities that could cause the fault.
At least HALF to 2/3 of all faults tend to be BT related, even if you have
already tried them and they have said otherwise. BT usually requires us to
prove that the system is not at fault before they will take more than a
brief look at the actual phone lines.
Sometimes just turning the system on and off can clear an annoying fault.
The same can be said of unplugging the phone from its socket and then
plugging it back in.
If you are experiencing problems dialing out or receiving incoming calls,
firstly turn the phone system off and on again, more often than not this
will clear the problem. If this fails to clear the problem then there may be
a problem with the actual telephone lines. This can be checked by ringing
154 and asking B.T. to check the lines for faults, the lines can be checked
there and then. If B.T. say there are no apparent faults please ring us and
an engineer will be sent out. It may also be worth putting a phone in the
power fail socket, if you have one, to see if the fault is still there. If the
fault appears on the power fail socket then it will definitely be a B.T. fault
as this socket bypasses the system completely.
If a phone stops working the best way to check it is to try it in another
socket. Please note that a normal phone will not work in a socket normally
used for a Panasonic keyset. You could also try a phone that you know
works in the socket that is suspect. This will show whether you need a
new phone or whether you need an engineer to look at the problem.
Should a phone stop ringing please check that the ringer has not been
turned off? On keysets this is done by changing the volume while the
phone is ringing (KXTD phone systems) or by checking a switch on the
back of the phone (KXTA phone systems). Normal telephones usually
have a switch on the back of the phone that alters the pitch of the ring as
well as a switch that alters the ringing volume. If the phone still fails to
ring please call us so we can get an engineer to look at the problem.