Lenovo x3550 M4 Installation And Service Manual page 157

AC power-supply LEDs
AC DC Error (!)
On Off
On Off
On On
DC power-supply LEDs:
Use this information to view DC power-supply LEDs.
The following illustration shows the locations of the power-supply LEDs on the dc
power supply.
Figure 90. DC power-supply LEDs
The following table describes the problems that are indicated by various
combinations of the power-supply LEDs on a dc power supply and suggested
actions to correct the detected problems.
Description
Off Power-supply not
fully seated, faulty
system board, or
the power supply
has failed.
On The power supply
has failed.
On The power supply
has failed.
Action
1. Reseat the power supply.
2. Follow actions in the "Power
problems" on page 161.
3. If the OVER SPEC LED on
the light path diagnostics is
lit, follow the actions in
"Light path diagnostics
LEDs" on page 132.
4. If the OVER SPEC LED on
the light path diagnostics is
not lit, check the error LEDs
on the system board and the
IMM2 error messages. Follow
steps in "Power problems"
on page 161 and "Solving
power problems" on page
169 until the problem is
solved.
Replace the power supply.
Replace the power supply.
Notes
Typically indicates a
power-supply is not
fully seated.
Chapter 4. Troubleshooting
139