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may lie with the first power supply bay and not the power supply module. Call Cisco Technical Assistance
Center (
) for further instructions.
b) If a second power supply is available, install it in the second power supply bay.
c) Check that the INPUT LED is on for the additional power supply. Check that the FAIL LED is off.
d) If the LEDs are not on, repeat the previous procedure to troubleshoot the second power supply
Step 4
Contact Cisco Technical Assistance Center.
If you are unable to resolve the problem, or if you determine that either a power supply or backplane connector
is faulty, contact Call Cisco Technical Assistance Center (
) for instructions.
Troubleshooting a DC-Input Power Supply
To help isolate a power subsystem problem, follow these steps:
Procedure
Step 1
The INPUT LED should be solid green for normal operation. If the INPUT LED is off, perform the following
steps:
a) Check the DC source.
1.
Check that the circuit breaker of the DC source is ON.
2.
Connect the cables to another power source if one is available. Verify that the source power is within
the acceptable specifications of the power supply.
3.
Check that you have connected both the DC inputs to a suitable DC source. The power supply module
is not designed to function with just one DC input.
4.
If you are using a single source, check that it is capable of providing 3500 W of DC-input power. If
it is two different sources, check that each source is able to provide 1750 W of DC-input power.
5.
Ensure that the DC source is capable of providing a minimum of -40 V to the input terminals of the
DC power supply module. .
b) Check the DC-input cable connections
1.
Check that the lugs are fastened properly and torqued to between 2.0 and 2.8 Nm.
2.
Check that the polarity of the DC-input cables is not reversed. For more information, see
Connection Guidelines for DC-Powered Systems, on page 37
3.
If you are using a separate source for each DC input, check that you have not crossed the cables
(reversed positive or negative inputs).
If the INPUT LED still fails to light, the power supply module is probably faulty. You may have
to replace it.
Note
Step 2
The OUTPUT LED should be solid green for normal operation. Blinking green indicates that the unit is asleep
in standby mode. If the OUTPUT LED is off, perform the following steps:
Cisco Catalyst 9400 Series Switches Hardware Installation Guide
133
Troubleshooting
Troubleshooting a DC-Input Power Supply