Lucent Technologies AT&T 7400B - Manual (Page 42)

CHAPTER 5: TROUBLESHOOTING DEFINITY Communications System
7400B Data Module
Page 5-2 User’s Guide
Symptom Problem Solution
All LEDs are off. Power is off. Check that the AC outlet is live.
Check that the power supply unit is
connected to the 7400B Data
Module and to the AC outlet.
POWER/TEST and DATA The data module has lost Check that the D8W cord is
LEDs flash together. communications with the connected between the LINE
PBX. connector of the data module and a
PBX wall jack. Note also that the
line from the PBX must be
properly administered for the
7400B Data Module.
Characters typed on If the SD LED does not Connect or replace the EIA-232-D
keyboard are not flash when keys on the cable between the data module and
displayed on the screen of terminal are pressed, the the local terminal device.
the terminal device. EIA-232-D cable is not
connected or not properly
wired.
If the SD LED flashes but Press [ Enter ] to start a new
the RD LED does not command line, and then type
flash, the command echo
atel [ Enter ]
option is turned off.
to turn on the command echo.
The SD and RD LEDs Press [ Enter ] to start a new
flash, but certain EIA command line, and then type
signal leads are turned off.
at&s0&c0 [ Enter ]
to ensure that the appropriate EIA
signal leads are turned on.