Troubleshooting The Fan Tray Assembly - Cisco Catalyst 9400 Series Hardware Installation Manual

Troubleshooting
Condition
Only one power supply module
is configured, and it is a
DC-input power supply module.
Multiple power supply modules
are configured (AC and DC
input).
and
3.3-VDC standby output of the
power supply modules (AC and
DC input) is inactive.
Multiple power supply modules
are configured (AC and DC
input).
and
3.3-VDC standby outputs of one
of the power supply modules is
active
3

Troubleshooting the Fan Tray Assembly

Note All fans must be operating or a failure will occur.
Environmental problems may initially appear to be problems with the fan tray. To help isolate a fan assembly
problem, follow these steps:
3
.
Regardless of whether one or more AC-input or DC-input power supply modules in the system is off
or on, if AC-input or DC-input power is applied, 3.3-VDC standby is active and distributed to all power
supply modules in the chassis.
Action Required to Restore Default Mode of the Power Button
1. Switch off the DC circuit breaker for at least three seconds.
2. Switch on the DC circuit breaker.
The FAIL LED is illuminated for two to three seconds.
Result: The power supply module enables output power automatically,
and the power button is in auto-on mode.
1. Switch off the DC circuit breaker of the affected power supply module
for at least three seconds.
2. Switch on the DC circuit breaker of the affected DC-input power
supply module.
The FAIL LED is illuminated for two to three seconds.
Result: The power button is in auto-on mode.
1. Press the power button of the affected DC-input power supply module
for two seconds, to turn it off.
2. Switch off the circuit breaker of the affected DC-input power supply
module.
3. Remove and reinsert the DC-input power supply module after having
its DC input physically disconnected or disabled for at least three
seconds.
4. Switch on the DC circuit breaker of the affected DC-input power
supply module.
Result: The power button is in auto-on mode.
Cisco Catalyst 9400 Series Switches Hardware Installation Guide

Troubleshooting the Fan Tray Assembly

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