Problem Solving
2–9
2.4.4
Interpreting the LED Indicators
Pass/fail results from the diagnostics are displayed on the LED indicators. Table 2–1
lists typical LED displays for various error conditions, along with probable causes
and suggested corrective actions. The flow chart in Figure 2–3 indicates steps you
can take to determine why a bridge is in the powered-down state. The flowchart in
Figure 2–4 describes how to troubleshoot the FDDI interface. For more information
on loopback testing, refer to Section 2.4.6. For replacement procedures of field-re-
placeable units (FRUs), refer to Chapter 3.
Table 2–1:
Problem Solving Via the LEDs
NOTE
Always turn off power before removing and replacing
any of the FRUs.
Symptom
Probable Cause
Corrective Actions
General:
One or more LEDs do not
Module(s) are not
Remove and reseat the logic modules
light during lamp test.
properly seated
(Section 3.3.2).
Bad module(s)
Replace the logic module(s) containing the
unlit LED(s) (Section 3.3.2).
All LEDs are off.
Power cord
Ensure that the power cord is connected to the
disconnected
bridge and to the ac outlet.
Circuit breaker
Reset the breaker. If it continues to trip, a more
tripped
serious problem is indicated.
Faulty power cord
Check the cord continuity and replace if necessary.
Power at wall outlet. Check the ac outlet circuit breaker. Verify that
correct power is available at the outlet. Move the
power cord to another outlet.
Blown power
In some countries, the connector to the ac outlet
connector fuse
contains a fuse. Replace if necessary. If the fuse
continues to blow, it indicates a more serious
problem.
