Avaya S8700 Maintenance Manual page 1498

Maintenance-Object Repair Procedures
3. Check to see if the fiber-optic cable is transmitting properly via the following
procedure on one of the out-of-service links, or use the
Fiber Links'' on page
a. Carefully record the symptoms (amber LED pattern and test failing)
b. Disconnect the transmit and receive fiber pair from the lightwave
c. Connect what was formerly the transmit fiber to the receive jack.
d. Connect what was formerly the receive fiber to the transmit jack.
e. Perform steps b, c, and d on the opposite end of the fiber and the
f. If the symptoms that were formerly occurring on the EI circuit pack
4. Determine whether the problem is due to a defective active Tone-Clock
circuit pack. Refer to the preceding list of symptoms to decide which
network contains the suspect active Tone-Clock.
!
8-776 Issue 1 May 2002
4-19.
that were occurring on the PN EI circuit pack and the PN EI circuit
pack or the connected CI circuit pack in the case of a Center Stage
system. Clearly indicate what symptoms are occurring on which
EI/SNI circuit pack.
!
CAUTION:
Before proceeding, note which is the current transmit fiber and
which is the current receive fiber for proper reconnection.
transceiver behind one of the EI circuit pack slots that is exhibiting
symptoms.
lightwave transceiver behind the connected EI or SNI circuit pack
slot.
that was exhibiting these symptoms are now occurring on the
connected EI or SNI circuit pack and vice versa, the fiber is
defective and should be replaced.
CAUTION:
If you remove the PN EI circuit pack that is active or that was active
when the PN was last in service, the Tone-Clock lead will revert to the
default value which will cause the Tone-Clock circuit pack located in
the A carrier to become the active Tone-Clock. This characteristic
can be deceiving. Replacing or reseating the active PN EI circuit
pack might restore the link(s) temporarily. However, if the Tone-Clock
circuit pack located in the B carrier was really the source of the
problem and not the EI circuit pack, then the link(s) will go down again
the next time a Tone-Clock switch to the Tone-Clock in the B carrier is
attempted (probably when the scheduled Tone-Clock switch occurs).
!
CAUTION:
If, after every link is restored, you suspect the problem might
have been due to a defective Tone-Clock circuit pack, switch to
this Tone-Clock at an appropriate time. If the Tone-Clock
circuit pack was the cause of the problem and the same EI
circuit packs are in place, the same link(s) will go down again.
''Fault Isolation for
555-233-143