Nortel Meridian 1 Manual page 187

Possible cause
Defective
telephone
Defective wiring
Defective digitone
receiver
Excessive
Digitone traffic
Action
If only one telephone is affected, replace it.
If there is still a problem with the telephone, go to the next possible cause.
If only one telephone is affected, make sure wiring is properly connected
and wires are not interchanged, crossed, or grounded:
— Check the wiring between the telephone and the cross-connect
terminal.
— Check the wiring between the PE shelf and the cross-connect
terminal.
If there is a wiring problem, correct it.
If there is still a problem with the telephone, go to the next possible cause.
If the condition is intermittent or more than one telephone is affected, test
the digitone receivers in the system by entering:
LD 34
DTR l s c u "l s c u" represents loop, shelf, card, and unit numbers of
the DTR.
Replace any units that fail the test.
If there is still a problem with the telephone, go to the next possible cause.
Additional digitone receivers may be required to handle the traffic in the
system. See Traffic measurement formats and output (553-2001-450).
Clearing telephone faults
Meridian 1 Fault clearing
Page 173 of 190