CANOGA PERKINS 2370 High-Speed Universal Fiber Optic Modem - Manual (Page 45)

EdgeAccess Universal Chassis System
Model 2370 Model User Manual 5-1
Chapter 5
Troubleshooting
Use the diagnostic procedures in this section to test and troubleshoot the 2370. Before starting the
diagnostics, obtain this equipment:
• Multimeter
• Fiber Optic Power Meter
• Short (1 m or less) fiber optic jumper cable
• Bit Error Rate Tester (BERT)
Table 21 lists troubleshooting strategies for various symptoms.
Table 21. Symptoms With Possible Causes and Actions
Symptom Possible cause(s) Corrective action
No power indicator on front
panel(s) No AC power Check AC power source
Defective modem Replace modem
Local or Remote sync error Faulty modem, cable or connector. If
the modems are configured in a tail
circuit (one is externally locked and
the other is slave), verify that the
externally locked modem has a clock
on its TT (or equivalent) leads that
matches its rate switch.
Run Loopback and BERT
tests
Cable loss exceeds modem
loss budget Faulty fiber optic cable Replace defective cable
Faulty fiber optic connector Polish or replace connector
Loopback test passes, but
modems will not pass data Modem not configured properly Check and correct switch
and jumper settings on all
devices
Interface cables damaged or wired
incorrectly Repair or replace cables
Modem fails BERT test
when optically looped back
to itself Faulty modem or electrical interface Replace faulty modem
Modem fails BERT when
looped locally Faulty modem or electrical interface Replace faulty modem