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Solving power problems

Use this information to solve power problems.

Power problems can be difficult to solve. For example, a short circuit can exist anywhere on any of the power distribution buses. Usually, a short circuit will cause the power subsystem to shut down because of an overcurrent condition. To diagnose a power problem, use the following general procedure:

  1. Turn off the server and disconnect all ac power cords.
  2. Check for loose cables in the power subsystem. Also check for short circuits, for example, if a loose screw is causing a short circuit on a circuit board.
  3. If the system-error LED on the system board is lit, complete the following steps:
    1. Check the IMM2 event log. To access the web interface, see Logging on to the Web interface.
    2. If a log indicates that there is a power rail failure, find the location of the failed power rail on the system board.
    3. Disconnect the cables and power cords to all internal and external devices (see Internal cable routing). Leave the power-supply cords connected.
    4. Remove each component that is associated with the failed power component, one at a time, restarting the server each time, until the cause of the failure is identified.
    5. Replace the identified component.
  4. Reconnect all power cords and turn on the server. If the server starts successfully, replace the adapters and devices one at a time until the problem is isolated.

If the server does not start from the minimum configuration, see Power-supply LEDs to replace the components in the minimum configuration one at a time until the problem is isolated.