Lenovo THINKSERVER 3821 - Manual (Page 147)

Power-supply LEDs
The following illustration shows the power-supply LEDs on the rear of the server.
For more information about solving power-supply problems, see “Solving power
problems” on page 123.
1 ac power LED
2 dc power LED
3 Power error LED
The following table describes the problems that are indicated by various
combinations of the power-supply LEDs and the power-on LED on the operator
information panel and suggested actions to correct the detected problems.
Chapter 6. Locating Server Controls and connectors 139