Messages and Troubleshooting
6-4 7510-A2-GB20-10
November 1997
Table 6-2. Troubleshooting (2 of 2)
Symptom SolutionsPossible Cause
Not receiving data;
DSU is not
responding.
DDS line rate/speed has
changed.
Excessive BPVs causing
DSU to become stuck in
Autobaud mode.
Excessive Loop Loss
causing DSU to become
stuck in Autobaud mode.
Verify that your subscriber loop is
running at 56 or 64 CC kbps.
Verify that the DSU is set to the
same rate as your subscriber
loop. (The DSU’s rate is
displayed on the Network
Interface Status screen.)
If getting Excessive BPVs, verify
that you do not have a bad cable.
If the cable is good, contact the
network provider.
If getting excessive Loop Loss
(dB)indications installa higher
If getting excessive Loop Loss
(dB) indications, install a higher
quality cable. Refer to Table D-2,
Model 7510 DSU LADS
Connection Distances, in
Appendix D.
If the DDS Line Rate (Kbps) field
shows Autobaud, the DSU may
be stuck in Autobaud mode.
Configure Line Rate (Kbps) for
56 or 64 kbps.
Run Loopback tests. Refer to
Running Network Tests
in
Chapter 5.
Power-Up Self-Test
fails. Only Alarm
LED is on after
power-up.
The DSU has detected an
internal hardware failure. Reset the DSU and try again.
Contact your service
representative.
Resetting the DSU
The DSU can be reset locally or remotely.
To reset the DSU, follow this menu selection sequence:
Main Menu
→

Control

→

Reset Device

The DSU reinitializes itself, performing a Device Self-Test. Refer to Table 4-3,
Self-Test Results Messages.
Displaying DSU Identity Information
To display the DSU’s system name, location, contact, serial number, model
number, and software and hardware revision numbers, follow this menu selection
sequence:
Main Menu
→
Status
→

Identity