Troubleshooting Isdn Lines - NEC ux5000 Hardware Manual

3.14.1.4 Troubleshooting ISDN Lines

Start
Verify the BRIU blade
is functioning.
Is the Live Status
LED on the BRIU
blade flashing green?
Yes
Is the ISDN Layer1
link established
(LD2, LD3 flashing)
on the BRIU blade?
Yes
Request the CO
perform a
loopback test of
the DSU. Any
problems found?
No
If an external DSU is
used, connect the
ISDN terminal to the
T-Point. Is it possible
to make a call?
Yes
Insert another BRIU blade
into the same slot in the
CCPU. Does it work?
Yes
The BRIU blade
may need repair.
Chapter 3
Release the Block
in Program 90--05
No
(enter 4) for the blade
and recheck operation.
Verify wiring between
main equipment and
CO line and between
No
the two UX5000
chassis (if installed).
Is the cable
Yes
wiring correct?
DSU may need repair.
Yes
T-Point portion of the external
No
DSU may need repair.
Check system programming
for the extension. Refer to the
UX5000 Software Manual if
No
necessary. Is it possible to
make a call?
The main equipment
(chassis/CCPU) may
need repair.
Figure 3-17: BRI Line Troubleshooting
Chapter 3 - Installing Extensions and Trunks
(chassis/CCPU) may
Remove the blade and
blade into the same slot.
The BRIU blade may
No
* If it still does not work,
replace the cable(s) and/
Yes
No
Main equipment
need repair.
No
insert another BRIU
Does it work?
Yes
need repair.
Redo the wires
correctly.
or connectors.
Stop
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