Troubleshooting guide

Troubleshooting Guide
114
Digital Trunks
Table 34: Digital Trunk Troubleshooting
Symptom Probable Cause Corrective Action
General
Excessive Bit Error
Rate.
Faulty programming. Make sure the system is programmed the same
as the CO, for B8Zs or AMI
Excessive Slips. Faulty programming. Ensure the Network Synchronization form is
programmed and the system is clocking
appropriately. Use the Netsync Summary
maintenance commands to determine if
synchronization is taking place, If not, use Net Set
1 to set off the first clock source or NET SET
AUTO to select the best available clock source.
After you choose a synchronization clock source
always use the NET SET AUTO command to
confirm.
System is not
Receiving Calls.
The DID trunk digit modification
number on the Trunk Attributes
form does not have anything
programmed in the absorb field. It
MUST have a minimum of 0, or no
calls will be accepted.
Ensure that there is an entry in the absorb field. It
cannot be left Blank.
Faulty ANI/DNIS programming. Check ANI/DNIS programming to ensure there
has not been confusion with a DID trunk. For
ANI/DNIS to work the digit must be received from
the Central Office as *ANI*DNIS*. If the digits are
not being received in this format, turn off the
ANI/DNIS in the Class of service Options.
Outgoing calls are
dropping after a couple
of minutes into the
conversation.
System is not receiving answer
supervision from the central office
and is timing out.
If the Central office cannot provide answer
supervision on answered calls go to the CO Trunk
Circuit Descriptor Assignment and change the
value in the field ”fake answer supervision after
outpulsing” to Yes.
Calls are connecting,
and the far end can
hear us but we cannot
hear them.
System is not receiving answer
supervision immediately from the
Central Office.
In the CO Trunk Circuit Descriptors form, change
the Supervision parameters in the value field
“audio inhibit until answer supervision after
outpulsing” to No.
Trunks are
programmed but are
appearing as
Unassigned with the
STAT location ID
command.
Card has not had the information
downloaded to update the status of
the trunks.
Download the information to the NSU at an
appropriate time.
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