Inter-Tel AXXESS Manual page 1315

Table 7-7. CO Trunk Troubleshooting Chart (Continued)
Symptom
Noise on CO trunk at all
stations
T1 trunks have frequent
"Controlled Slip" and
"Out-Of-Frame" errors
CO trunk remains seized
after a call has been ended
Ground start trunks not
functioning properly
CO Trunk Issues
INTER-TEL
Possible Cause
Defective CO trunk
Defective trunk card
Defective power supply
Defective CPC or CPU Card
Line Build-Out (LBO) setting
incorrect
Defective T1 trunk
Defective T1C
Characteristic of some ESS
central offices
IC-CO or CO-CO Disconnect
timer value set too long
Defective CO trunk
Defective station instrument
Defective trunk card
Defective CPC or CPU Card
System not properly grounded
Tip and ring are reversed
Programming error
® ®
AXXESS MANUAL VERSION 11.0 – May 2008
Corrective Action
At the CO block, remove the bridging clips for the
trunk. On the telco side of the block, use a test set
to verify the CO trunk connection. Also, move the
CO trunk to a known good CO circuit. If the problem
follows the trunk, contact the telephone company.
Replace the associated trunk card.
See INSTALLATION, page 3-83
the power supply electrical test. Replace the power
supply if faulty.
See page 7-3 for LED and system voltage informa-
tion. Replace the card if faulty.
Use T1 Diagnostics to determine the current LBO
status. Then use T1 Programming to change the
setting. See page 6-126 in PROGRAMMING.
Check for improper connection. If the problem per-
sists, contact the T1 provider.
Replace the associated T1 card.
Central office must provide disconnect signal. Or,
install a trunk release module available from most
supply houses.
Central office disconnect signal was not detected by
IC-CO or CO-CO Disconnect timer. Default value of
the IC-CO timer is 0.6 seconds; the CO-CO timer is
0.35 seconds. See page 6-329
At the CO block, remove the bridging clips for the
trunk. On the telco side of the block, use a test set
to verify the CO trunk connection. Also, move the
CO trunk to a known good CO circuit. If the problem
follows the trunk, contact the telephone company.
Replace the station instrument and/or perform the
keyset self-test as outlined in INSTALLATION,
page 3-182.
Replace the associated trunk card.
See page 7-3 for LED and system voltage informa-
tion. Replace the card if faulty.
Verify that the system AC circuit is isolated and ded-
icated (see page 3-10 in INSTALLATION) and check
for proper grounding (see page 3-81
TION).
At the CO block, check to make sure that tip and
ring are not reversed. See INSTALLATION,
24. Unlike loop start trunks, ground start trunks are
polarity sensitive.
Ensure that the trunks are identified correctly as
ground start trunks. See PROGRAMMING,
244.
Troubleshooting
or 3-92, to perform
in PROGRAMMING.
in INSTALLA-
page 3-
page 6-
Page 7-35
7