DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126
Issue 4
June 1999
Alarms, Errors, and Troubleshooting
5-104Packet Bus Fault Isolation and Repair
5
NOTE:
The Tone/Clock circuit pack should be the next-to-last one checked. (The
TN771D must be reseated after the Tone/Clock is reinstalled.) Refer to
Procedure 3 for the TN768 or TN780 Tone/Clock circuit pack in a PPN with
duplicated SPEs.
If the packet bus problem is present when the circuit pack is inserted, but is
resolved when the circuit pack is removed, either the circuit pack or the
backplane pins in that slot caused the problem. If the backplane pins are intact,
replace the circuit pack. Keep in mind that there may be more than one failure
cause.
In Procedure 2, you may try one circuit pack at a time, or multiple circuit packs
simultaneously. The allowable level of service disruption should guide this
choice. If the entire port network can be disrupted, trying large groups of circuit
packs will save time. If traffic is heavy, trying 1 circuit pack at a time is slow but
will minimize outages.
If the TN771D Standalone mode does
not
indicate packet bus faults, perform
Procedure 2 for
only the port
circuit packs (purple slots) listed in Table 5-8 in
Procedure 1. In this case, you need not check for problems with the backplane
pins. It is sufficient to determine whether the problem is resolved by removing
circuit packs.
If you decide to remove multiple circuit packs, consider working with an entire
carrier at a time to more quickly and reliably determine which circuit packs are
not
the source of trouble. Any circuit packs, (packet or non-packet), that have
been recently inserted should be checked first. Packet circuit packs should be
checked before non-packet circuit packs.
1. Remove one or several circuit packs.
2. Determine if the packet bus fault is still present. If not, go to step 4.
3. If the packet bus fault is still present:
a. Determine if the backplane pins in the removed circuit pack’s slot
are bent using the output from the Maintenance/Test standalone
mode and the backplane illustrations which appear earlier in this
discussion.
b. If the backplane pins are bent:
Power down the carrier (see ‘‘Replacing a BIU or Rectifier’’
),
straighten or replace the pins, reinsert the circuit pack and restore
power. Repeat Step 2 for the same circuit pack.
c. If the backplane pins are not bent:
Reinsert the circuit pack(s), and repeat this procedure for the next
set of circuit packs.
