HP Proliant ML350 Gen9 doesn't start

Please refer to HPE ProLiant ML350 Gen9 Server - LED Indicators for interpreting the LEDs correctly. Count how many times the power fault LEDs blink to find the faulty component:

  1. System board
  2. Processor
  3. Memory
  4. Riser board PCIe slots
  5. FlexibleLOM
  6. Removable HPE Flexible Smart Arraycontroller/Smart SAS HBA controller
  7. System board PCIe slots
  8. Power backplane or storage backplane
  9. Power supply

If you have warranty left, just open a support ticket with HPE and they will replace the component for you. Otherwise, replace or remove the component as applicable for you.