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DEFINITY Enterprise Communication Server Release 9
Installation and Maintenance for Survivable Remote EPN
555-233-121
Issue 2
November 2000
SREPN Maintenance
2-35
Fault isolation procedures
2
8. Connect the transmit and receive cables together using the fiber optic
coupler (Comcode 407643014, provided in Maintenance Kit #30) to create
a loop as shown in
Figure 2-19
.
Figure 2-19.
Manual loopback with fiber optic coupling
9. Go to the front of the cabinet and inspect the yellow LED.
a. If the yellow LED flashes on at a rate of once per second, the
Expansion Interface or Switch Node Interface circuit pack or
transceiver should be replaced.
b. If the yellow LED flashes on at a rate of 5 times per second, the
Expansion Interface or Switch Node Interface circuit pack or the
lightwave transceiver may need replacement. This condition may
also be due to a faulty system clock on the network containing the
Expansion Interface circuit pack or in the switch node carrier
containing the SNI.
c. If the yellow LED was blinking before starting this procedure and the
yellow LED is not blinking now, this circuit pack (Expansion Interface
or Switch Node Interface) and the lightwave transceiver are
functioning properly.
Figure Notes
1. Fiber optic coupling (Comcode 407643014)
RX
RX
TX
TX
cydfloop LJK 032398
Back of cabinet
1