Nortel Meridian 1 Succession 1000 Description page 65

Table 9
M2317 trouble-locating procedures (Part 2 of 3)
Step Action
ISDLC failure
1 Go to the system maintenance terminal (TTY or CRT) and check for displayed error
and location codes. An "NWS 401 L S C" or an "NWS 501 L S C U" code indicates that
the automatic (routine) diagnostic test has detected a fault.
Check for the following indications:
L = faulty circuit card (ISDLC card) loop number
S = circuit card location (shelf number)
C = number of the faulty circuit card
U = unit number of a faulty telephone (appears only in conjunction with the NWS 501
code)
2 Replace the faulty components.
Try to establish a call. If unsuccessful, check the telephone.
Telephone installation
Telephones and Consoles
Page 65 of 532
Description