Troubleshooting guide

Hardware
45
After changing NSU from T1 to
E1, NSU remains unassigned.
NSU does not reflash. • Flash the NSU (refer to Technical
Bulletin 58004932)
OR
• Delete datetag.txt via ftp
OR
• From the debug terminal, issue force dl
for the NSU.
NSU fails to boot, with an error
message.
Boot line timeout.
Universal NSU programming is
not complete.
1. Ensure that the NSU is programmed as
a Universal T1 or E1 (not T1 or CEPT).
2. Program the proper link descriptor with
the proper integrated access, and
assign to the corresponding NSU unit
(for example: ISDN node for PRI
protocol, T1D4 for T1D4, DPNSS for
MSDN).
3. Program at least one trunk.
PRI/QSIG NSU fails to boot. Database not compatible with new
load.
1. Connect IMAT to the PRI NSU and start
IMAT.
2. Download the database from the NSU
to IMAT.
3. Save the database from IMAT to the
NSU.
4. A message appears asking if you want
to convert the database. Select Yes.
5. When the database has finished saving,
reset the NSU.
Unable to FTP into the NSU. Release 4.1 and later requires a
username and password to login.
Enter:
username, mitel
password, passwd1
NSU is up, but L0 or L1 LED is
solid red.
No physical connection to far end. 1. Verify and fix wiring.
2. Check DIP Switch 6. If it is UP, set it to
DOWN to see if this makes any
difference (see “Universal and R2 NSU
DIP Switch Settings” in the “Hardware
Reference” chapter of the MCD
Technician’s Handbook).
NSU is up, but L0 or L1 LED is
flashing green.
Layer 2 protocol mismatch. Change protocol through IMAT
Distorted voice or loud noise
on NSU trunks.
Voice encoding is not set properly. Change Voice encoding in the link
descriptor to invert for T1, and ADI invert
for CEPT (this does not apply to
Embedded PRI).
Set termination impedance switch
correctly (75 ohms or 120 ohms).
Table 11: Service Unit Troubleshooting
Symptom Probable Cause Corrective Action
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