Avaya MCC1 Maintenance Procedures page 274

Packet and serial bus maintenance
G650 Serial Bus fault detection and isolation
cable assemblies and TDM/LAN bus terminators are replaced. If this action does not resolve the Serial
Bus fault, the carriers are reconfigured so that certain carriers are disconnected from the Serial Bus. This
is done by moving the TDM/LAN bus terminators (AHF110) on the carrier backplane. To terminate a
Serial Bus at the end of a particular carrier, the Serial Bus cable that connects the carrier to the next
carrier should be unplugged and replaced with the TDM/LAN Bus terminator. When the length of the
Serial Bus is modified, the A carrier IPSI-2 circuit pack that is essential to the Serial Bus operation and
Serial Bus maintenance must still be connected to the new, shortened Serial Bus.
After making and verifying the cabling changes, restore power to the port network. Circuit packs in
carriers that are not part of the shortened bus are not inserted, and as a result these circuit packs are
alarmed. Ignore these alarms for now. All alarms should be resolved when the cabinet is restored to its
original configuration.
Procedure 2 is organized into two parts:
• Part 1 attempts to clear the Serial Bus fault by replacing all the bus cabling and terminators within
a port-network.
• Part 2 attempts to isolate the fault to a particular carrier by extending the Serial Bus from the A
carrier to additional carriers one at a time.
!
Remove power from the entire port network before removing any cables or terminators. Failure to
follow this procedure can cause damage to circuit packs and power supplies and can be hazardous
to the technician.
Part 1
1 If spare TDM/LAN cable assemblies and TDM/LAN Bus Terminators are not available, go to
Part 2 of this procedure.
2 Power down the port network.
3 Replace all of the TDM/LAN cable assemblies and both TDM/LAN bus terminators.
4 Restore power to the port network.
5 Run the
is still present.
6 If the Serial Bus fault is resolved, the procedure is completed. Otherwise, go to
Part 2
1 Terminate the TDM/LAN Bus so that it extends only across the carrier that contains the A carrier
IPSI-2.
2 Determine if the Serial Bus fault is still present by running the
cabinet command.
3 If
list configuration power-supply
TDM/LAN/Serial Bus to another carrier, and repeat the procedure in the previous step. When a
carrier that causes the fault to recur is added, perform Procedure 2 for only the circuit packs in that
carrier.
4 If
list configuration power-supply
procedure has resolved the problem, the added carrier(s) are defective and must be replaced.
274
WARNING:
list configuration power-supply
cabinet command to determine if the Serial Bus fault
list configuration power-suppl
cabinet doesn't fail to show any power supplies, extend the
cabinet fails to show any power supplies, and neither
Part 2.
Maintenance Procedures
December 2003
y