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System pulse LEDs

Use this information to diagnose possible errors that are indicated by the system pulse LEDs.

The following LEDs are on the system board and help you to monitor 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
LEDDescriptionAction
FPGA heartbeatPower-on and power-off sequencing
  1. If the LED blinks at 1 Hz, it is functioning properly and no action is necessary.
  2. If the LED is not blinking, (trained technician only) replace the system board.
IMM heartbeatIMM2.1 heartbeat boot process
The following steps describe the different stages of the IMM2.1 heartbeat sequencing process.
  1. When this LED is blinking fast (approximately 4 Hz), this indicates that the IMM2.1 code is in the loading process.
  2. When this LED goes off momentarily, this indicates that the IMM2.1 code has loaded completely.
  3. When this LED goes off momentarily and then starts blinking slowing (approximately 1 Hz), this indicates that IMM2.1 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, (trained technician only) replace the system board.