Avaya S8700 Maintenance Manual page 1179

CO-TRK (Analog CO Trunk)
Table 8-184. CO Trunk Errors with No Tests
Error Aux
Type Data
1 57347
257 50176
513 57364
769 57392
2561 57345
2817 57360
555-233-143
Error Description and Repair Action
Port error. Ringing without ground. This error is detected on an incoming
call on a ground-start CO trunk. The CO trunk circuit pack has not detected
a Tip ground before ringing current is detected. This may indicate that the
ground detector is not working. However, the call will be accepted. Busyout
the affected port, and run a long test. Observe the test results. If any tests
fail, refer to the description of the tests and the associated error codes.
Release the port. If users continue to report troubles, check for other errors
and make test calls to determine whether the problem should be referred to
the CO.
Battery reversal detected. This is usually caused by the CO (often seen with
step-by-step and cross-bar offices in connection with outgoing calls). This is
detected if the direction of the loop current changes from normal to reverse
for at least 40 msec. Could occur if the trunk was just installed and for some
reason the Tip and Ring wires were reversed at the PBX. If battery reversals
occur during dialing, wrong numbers may result. Refer problem to CO. Ask
them to remove the battery reversal option.
Ground detector stuck active. After several occurrences, an on-board minor
alarm is generated. Run the short test sequence. If test aborts with Error
Code 1000, disconnect Tip and Ring and repeat short test. If test still aborts,
replace circuit pack. If test passes, refer problem to CO. If any other error
code is received, pursue that problem.
CO not releasing after call is dropped from PBX end (TN747B), or the loop is
not open after a disconnect (TN765). After several occurrences, an off-board
(TN747B) or on-board (TN465) warning alarm is generated. Refer problem
to CO.
Single polarity ringing current. This error results from abnormal ringing
current, but does not prevent the incoming call from being accepted. One
cause could be that the reverse current detector associated with the port is
failing. (Will not be detected by any tests.) Another cause could be that
normal current is not detected. In this case, neither incoming nor outgoing
calls can be completed, and the dial tone test will also fail. The last cause
could be that certain types of noise are present on the CO line during the
silent period of ringing. First check for other errors. If the count for this error
is very high (255), and every test passes, then either the reverse current
detector is defective or the CO line is noisy. If the CO line is suspect, make
Tip and Ring observations. If the line is determined to be noisy, refer the
problem to the CO. If the reverse current detector is defective, ignore this
error.
Ground but no ringing. This error occurs on an incoming call on a
ground-start trunk. If ringing is not detected within 5 seconds of the Tip being
grounded, the call is still accepted. If the CO is of the No. 5ESS. switch
type, ringing delays of more than 5 seconds during heavy traffic are fairly
common. Check for other errors.
Continued on next page
Issue 1 May 2002 8-457