Problem Solving
2–11
Table 2–1 (Cont.): Problem Solving Via the LEDs
Symptom
Probable Cause
Corrective Actions
FAN FAULT on.
Fan connections
Check fan cable connections at the power supply.
Fan failure
Replace fan assembly (Section 3.3.5).
Fan power failure
Replace power supply module (Section 3.3.4).
DC_OK off.
Power supply fault.
Replace power supply module (Section 3.3.4).
NI Module LEDs:
NI_BAD remains on
External Loopback
Check the Enable External Loopback switch.
(and AP_BAD is off).
switch
The switch must be in the OFF (up) position
for normal bridge operation.
Defective NI module Replace the NI module (Section 3.3.2).
FI module is causing Replace the FI module (Section 3.3.2).
NI module to fail
NI_BAD blinking.
Incompatible
Load compatible firmware.
firmware loaded
FWDn blinking.
Port n in broken
Check the external connection to the NI port.
state
Perform external loopback tests.
Check the transceiver or DELNI (if AUI is selected).
FWDn off.
Port n in preforward- Wait 1 minute and verify that the bridge goes into
ing or backup state
forwarding state, indicating proper bridge operation.
Check line costs and enabling state using
management software.
Check the spanning tree topology using network
management software.
EXT_PWR_OK off.
AUI cable
Check the AUI cable(s) for a short by temporarily
removing each cable and observing if the LED
turns on. If it does, check the cable and the
transceiver at the other end of the cable.
Defective NI module Replace the NI module (Section 3.3.2).
EXT_PWR_OK off
(and DC_OK off).
12 V power supply
Replace the power supply module.
