System Interconnect Status Indicators - Compaq ProLiant 8500 Setup And Installation Manual

The PCI Hot Plug Interface board cables are properly connected to the
I/O board.
The PCI Hot Plug Interface boards are properly seated on the chassis
rear I/O panel.

System Interconnect Status Indicators

To prevent damage to critical system components, the ProLiant 8500 Server
will not power up if it senses that certain components are not installed, or are
installed incorrectly. The system interconnect status indicators provided with
ProLiant 8500 Server provide a closed-loop checking mechanism for verifying
proper component mating between critical server components. These
indicators are located in the I/O Module in front of the system fans. They are
operated using standby power provided by the power supplies.
If a light is on, reseat the component represented by the indicator. Labels next
to the LEDs identify the component causing the problem. Refer to the hood
labels for component location.
Initial Startup and Troubleshooting 8-3