M2000 Trouble-Locating Procedures - Nortel Meridian 1 Manual

Page 44 of 224 Telephones
Table 7
M2000 trouble-locating procedures (Part 1 of 2)
Data communication failure
1 If voice communication is normal but data communication fails, check for dc output
voltage at power supply connector pins or replace power supply plug-in transformer.
Attempt to make a data call from the terminal keyboard. If not successful, proceed with
step 2.
2 Remove the transformer from the AC receptacle, unplug the 5-pin power supply
connector at the back of the telephone, and replace the data option circuit board (see
Procedure 73 and Procedure 74). Reconnect the data option power supply.
Make a new attempt to start a data call. If trouble persists, continue with the ISDLC
failure procedure.
ISDLC failure
1 Check the Meridian 1 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 pack 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 faulty components.
Try to establish a call. If unsuccessful, check the telephone.
553-3001-215 Standard 10.00 June 1999