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Chapter 7: Troubleshooting
3.Connect another piece of functioning ISDN equipment to the ISDN line.
4.With the ISU 512 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 ISDN the line supports Dynamic TEI allocation. Tell them that you have an NT1 and ter- minal adapter device connected to the ISDN line.
IF THE DISPLAY READS TEI2
Outside of North America, only one TEI is usually assigned per basic rate line.
If the ISU 512 continues to read TEI2, the ISU 512 has completely initialized the first phone number but is unable to establish Logical Layer 2 for the second phone number. The problem is in one or more of the following places:
•The ISU 512 software setup
•The software setup of the telephone service provider
To isolate the problem, use the following procedure:
1.Make sure that the ISU 512 is set up with the correct SPID and LDN by se- lecting CONFIG, Netw. options, Dial Line, Terminal ID, and SPID/ LDN.
2.Try swapping SPID1 with SPID2 and LDN1 with LDN2, SPID3 with SPID4 and LDN3 with LDN4, SPID5 with SPID6 and LDN5 with LDN6, and SPID7 with SPID8 and LDN7 with LDN8. Determine if the problem is the second phone number or the quantity of phone numbers.
3.Connect another piece of functioning ISDN equipment to the ISDN line.
4.With the ISU 512 connected to the ISDN line and powered up, talk to your service provider's repair group and inform them you have an ISDN basic rate line that appears physically OK but has no Terminal Endpoint Identi- fier (TEI). Ask them to check the ISDN line translation and ensure that the ISDN line supports dynamic TEI allocation. Inform them an NT1 and ter- minal adapter device are connected to the ISDN line.
64 | ISU 512 User Manual |