Lenovo THINKSERVER 3797 - Manual (Page 50)

2. To view the light path diagnostics panel, slide the latch to the left on the front of
the operator information panel and pull the panel forward. This reveals the light
path diagnostics panel. Lit LEDs on this panel indicate the type of error that has
occurred.
The following illustration shows the light path diagnostics panel.
Note any LEDs that are lit, and then push the light path diagnostics panel back
into the server.
Look at the system service label on the top of the server, which gives an
overview of internal components that correspond to the LEDs on the light path
diagnostics panel. This information and the information in “Light path diagnostics
LEDs” on page 44 can often provide enough information to diagnose the error.
3. Remove the server cover and look inside the server for lit LEDs. A lit LED on or
beside a component identifies the component that is causing the error.
The following illustration shows the LEDs on the system board.
42 ThinkServer RD220 Types 3729, 3779, 3797, and 3798: Hardware Maintenance Manual