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ac power-supply LEDs

Use this information to view ac power-supply LEDs.

The following minimum configuration is required for the dc LED on the power supply to be lit:
  • Power supply
  • Power cord
Note
You must turn on the server for the dc LED on the power supply to be lit.
The following illustration shows the locations of the power-supply LEDs on the ac power supply.
Figure 1. ac power-supply LEDs
ac power-supply LEDs

The following table describes the problems that are indicated by various combinations of the power-supply LEDs on an ac power supply and suggested actions to correct the detected problems.

ac power-supply LEDsDescriptionActionNotes
acdcError (!)
OnOn / BlinkingOffNormal operation.  
OnBlinkingOffZero Output mode The zero output mode is used to configure the power supply behavior as standard redundant mode or zero-output mode by the host system. When the power supply is configured to this mode, minimal power consumption is maintained. At the same time, the power supply will keep its fan rotating, and the PSU LED should blink at a rate of 1 Hz.
OffOffOffNo ac power to the server or a problem with the ac power source.
  1. Make sure that the ac power source meets the minimum voltage requirement for the installed power supplies.
  2. Make sure that the power cord is connected to a functioning power source.
  3. Restart the server. If the error remains, check the power-supply LEDs.
  4. If the problem remains, replace the power supply.
This is a normal condition when no ac power is present.
OffOffOnThe power supply has failed.Replace the power supply. 
OffOn / BlinkingOffThe power supply has failed.Replace the power supply. 
OffOn / BlinkingOnThe power supply has failed.Replace the power supply. 
OnOffOffPower supply not fully seated, faulty system board, or the power supply has failed.
  1. Reseat the power supply.
  2. Use the Power Configurator utility to ensure that current system power consumption is under limitation. For more information and to download the utility, go to http://www-03.ibm.com/systems/bladecenter/resources/powerconfig.html.
Typically indicates a power-supply is not fully seated.
OnOffOnThe power supply has failed.Replace the power supply. 
OnOn / BlinkingOnThe power supply has failed.Replace the power supply. 
Note
When the dc LED is blinking at a 1 Hz rate, the PSU is at STANDBY mode. That is, no dc power output is from this PSU.