3Com AccessBuilder 500 User Manual page 69

Malfunction
The ISDN OK LED
does not light.
If other LEDs do
not light during
operation of the
unit.
The local unit
does not connect
to the remote
unit.
Remedy
Follow the procedures as outlined for
not light."
a) Ensure that the AccessBuilder 500 is powered up and the
POWER LED is lit.
b) Confirm that the ISDN UTP cable is correctly connected,
and that the cable is attached to the socket marked
ISDN.
c) Confirm that the ISDN line socket that is connected to
the unit is conveying an ISDN service.
d) Try making an ISDN call using a telephone connected to
the ISDN line to confirm if the line is operational.
e) If the LED still fails to light, plug the UTP cable into an
alternate ISDN service socket to confirm that it functions.
f) Try using an alternate UTP cable to connect the unit to
the ISDN service socket.
During normal operation the remaining unit LEDs should
light and extinguish depending on the action being taken. If
the LEDs fail to light in accordance with their function (refer
to "Front Panel" on page
3Com reseller.
a) Check the connections between the unit, the network, or
PC and the ISDN line.
b) Confirm that the line is working by connecting a
telephone to the ISDN line to make a call.
c) Check that the number which you are dialling is
connected to the remote unit and that the unit is
configured to be able to answer calls.
Troubleshooting
"The POWER LED does
1-9), then contact your supplying
1-49