Troubleshooting Dial Tone Problems - Nortel DMS-100 Series Maintenance Manual

8 The procedure is complete.

Troubleshooting dial tone problems

After you power up the RLCM-EDC verify that one or both LCM units are
in service. Check the line subgroups (LSG) to verify the subgroups have
dial tone. If the LSGs do not have dial tone, use the following procedure to
troubleshoot the source of dial tone failure.
1 If the even line subgroups (LSG) do not have dial tone, reseat and/or
replace the NT6X52 card in unit 0.
2 If the odd LSGs do not have dial tone, reseat and/or replace the NT6X52
card in unit 1.
3 If LSGs 0 through 9 do not have dial tone, verify with a voltmeter that
TB1 lug 7 reads –48 V. This terminal block is on the back of the frame
supervisory panel (FSP). This voltage is the talk-battery supply for these
drawers. This voltage comes from the power distribution center (PDC)
for this frame. Check the fuse in the PDC if the voltage is not present.
4 If LSGs 10 through 19 do not have dial tone, verify with a voltmeter that
TB1 lug 8 reads –48V. This voltage is the talk-battery supply for these
drawers.
5 If you do not have dial tone, contact the next level of support.
6 The procedure is complete.
Advanced troubleshooting procedures 10-11
DMS-100 Family Maintenance Manual ABSK007