AT&T MERLIN LEGEND Installation & Maintenance Manual page 530

Maintenance and Troubleshooting
Table 5-2 Continued
Error Screen
Code Description
7402
LOOP
CONTROL
BIT NOT
SET
7403
NO LOOP
7404
STUCK
RINGING
7801
NOT IN
NORMAL OP
MODE
5-52 Troubleshooting
Possible Cause
No Ioop current
No loop current
Continuous ringing
from CO
AC power cross
During background
port board check,
system detected
port board that was
not in normal
operation mode.
Solution
Test the line/trunk with a
single-line telephone. If
the problem is not in the
Iine/trunk, swap the
positions of similar
line/trunk and station
modules. If the problem
follows the module,
replace the Iine/tnmk
and station module.
Test the line/trunk with a
single-line telephone. If
the problem is not in the
line/trunk, swap the
positions of similar
line/trunk and station
modules. If the problem
follows the module,
replace the line/trunk
and station module.
Test the line/trunk with a
single-line telephone. If
the problem is not in the
Iine/trunk, swap the
positions of similar
Iine/trunk and station
modules. If the problem
follows the module,
replace the line/trunk
and station module.
problem persists,
If
check or replace
module.