NEC UNIVERGE NEAX 2000 IPS, Maintenance Manual

Page: 223 / 262

CHAPTER 2 TROUBLESHOOTING
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NWA-008847-001 Rev.3.0
a6ch2001.fm
Dial Tone is not returned from
distant office.
In case of COT card (1) Disconnect the trunk from the line
on the MDF.
(2) Connect a test telephone set to the
C.O. line (distant office side) on the
MDF.
(3) If Dial Tone is returned by going
off-hook on the test telephone set,
check for trouble with wiring on the
MDF and the trunk card.
(4) If not, there is a problem with the
distant office or the C.O. line.
(1) Trunk card.
In case of ODT card (1) Disconnect the trunk from the line
on the MDF.
(2) To perform a Loopback Test, make
a back to back connection of the
trunk card and another trunk within
the system at the MDF.
NOTE:
This test only works when the
trunks are assigned for type V
operation.
A
B
CHECK
SW MDF
TRUNK
To Distant Office
Test Telephone Set
REPLACE
CHECK
FAULT DIAGNOSIS AND TROUBLESHOOTING