Avaya S8700 Maintenance Manual page 1497

EXP-INTF (Expansion Interface Circuit Pack)
If a Tone-Clock in an PN that does not provide the current on-line
synchronization reference (see status synchronization) is providing an
invalid system clock:
In a direct connect configuration, the PN EI circuit pack amber LED will
blink quickly (Fiber Out-of-Frame condition - 0.1 seconds on, 0.1 seconds
off).
Test #238 fails on this EI circuit pack.
In a CSS configuration, the SNI connected to the PN EI circuit pack blinks
its amber LED quickly (Fiber Out-of-Frame condition - 0.1 seconds on, 0.1
seconds off).
The PN EI circuit pack amber LED blinks slowly (In-frame, No Neighbor
condition - 0.5 seconds on, 0.5 seconds off).
If the PN is in service, Test #237 fails on this EI circuit pack, but Test #238
passes.
These symptoms can also be the result of other problems (for example, one half
of the fiber being unable to transmit data). If the system exhibits these symptoms,
execute the following procedure:
1. Verify that the PN stays down for at least 1 minute.
If the EAL comes back in service after a short time, without switching the
active Tone-Clock, the problem was probably that the on-line
synchronization source became invalid (See SYNC Maintenance
documentation for more information).
However, if the EAL(s) have not come back into service after a minute, the
synchronization source is not the cause of the problem. Proceed to step 2.
2. Check for errors via the display errors command with the Category field
set to tone and the Active Alarms field set to n. Some of the alarms on PN
objects might have been resolved if the PN went down. Refer to the
appropriate MO Maintenance documentation for descriptions of any of the
errors occurring at about the same time as the EXP-PN errors, SYS-LINK
errors against EAL s, RNLs, or LNLs, or FIBER-LK (769, 1025, or 1281)
errors. Resolve any active alarms. Also, if Error Type 18 was logged
against the SYNC MO when the PN went down, the problem was probably
that the synchronization on-line reference became invalid. Since reference
switching was disabled, the Tone-Clock did not switch from the invalid
reference. Therefore, the Tone-Clock circuit pack put out a system clock
that was "out of spec." Issue the enable synchronization-switch
command. If the PN is down, reseat the Tone-Clock circuit packs on the
PN. This action should restore the PN to service.
Execute Steps 3 and 4 in the order most convenient to you and least
destructive to the customer.
555-233-143 Issue 1 May 2002 8-775