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System pulse LEDs

The following LEDs are on the system board and monitors the system power-on and power-off sequencing and boot progress.

See System-board LEDs for the location of these LEDs.
Table 1. System pulse LEDs
Enclosure management heartbeatPower-on and power-off sequencing.
  1. If the LED blinks at 1Hz, it is functioning properly and no action is necessary.
  2. If the LED is not blinking, (trained service technician only) replace the system board.
IMM heartbeatIMM heartbeat boot process.

The following steps describe the different stages of the IMM heartbeat sequencing process.

  1. When this LED is blinking fast (approximately 4Hz), this indicates, that the IMM code is in the loading process.
  2. When this LED goes off momentarily, this indicates that the IMM code has loaded completely.
  3. When this LED goes off momentarily and then starts blinking slowing (approximately 1Hz), this indicates that IMM is fully operational. You can now press the power-control button to power-on the server.
  4. If this LED does not blink within 30 seconds of connecting a power source to the server, complete the following steps:
    1. (Trained service technician only) use the IMM recovery jumper to recover the firmware (see System-board switches and jumpers).
    2. (Trained service technician only) replace the system board.