ADTRAN 1203086L1, Manual

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Chapter 8. Troubleshooting
61203086L1-1 ISU 512e User Manual 8-3
IF THE DISPLAY READS TEI1
If the ISU 512e reads TEI1 , then the ISU 512e is physically connected
to the local telephone service provider but is unable to establish Logi-
cal Layer 2. The problem is in one or more of the following places:
• The ISU 512e software setup
• The telephone service provider's software setup
• Hardware configuration if the line is extended from the switch
To isolate the problem, use the following procedure:
1. Ensure the ISU 512e is set up for the correct switch protocol.
2.
Ensure ISDN line quality is satisfactory by checking for near- and
far-end block errors (NEBEs and FEBEs).
If the counts are non-zero, there may be a physical link problem
(probably Layer 1 setup) caused by one or more of the following:
• The ISU 512e software setup
• The ISU 512e hardware
• CPE wiring
• Wiring from the telephone service provider
• Hardware of the telephone service provider
• Software setup of the telephone service provider
3. Connect another piece of functioning ISDN equipment to the
ISDN line.
4. With the ISU 512e connected to the ISDN line and powered up,
talk to your service provider's repair group and tell them you
have an ISDN basic rate line that appears physically OK but has
no terminal endpoint identifier (TEI). Ask them to check the line
translation and ensure that the ISDN line supports Dynamic TEI
NEBE/FEBE count may indicate a non-zero number
during test initialization. Press
0
on the front panel
NEBE/FEBE screen and wait for several minutes.