Lenovo ThinkServer RD440 - Manual (Page 72)

Note: Depending on the model, your server might look slightly different from the illustrations in this topic.
The server is designed so that LEDs remain lit when the server is connected to an ac power source but is not
turned on, if the power supply is operating correctly. This helps you to isolate problems when the server is not
turned on. Many errors are first indicated by a lit error LED on the diagnostic panel of some server models. If
an LED is lit, one or more LEDs elsewhere in the server might also be lit to direct you to the source of the error.
The following illustration shows the TMM status LED and system fan error LEDs on the system board.
Figure 42. System board LEDs
1 TMM status LED (also known as BMC status LED)
This LED indicates the status of the onboard ThinkServer Management Module (TMM, also known as BMC).
TMM status LED Color Description
On Green The TMM is not ready.
Off None The TMM has no power or has failed.
Blinking Green The TMM is working.
2 - 6 System fan error LEDs
When a system fan error LED on the system board is lit, it indicates that the corresponding system fan is
operating slowly or has failed. To solve the problem, you might need to reinstall or replace the system fan.
See “Replacing a system fan” on page 187. If it is a system board problem, contact the Lenovo Customer
Support Center.
60 ThinkServer RD440 User Guide and Hardware Maintenance Manual