v Follow the suggested actions in the order in which they are listed in the Action column until the problem
is solved.
v See Chapter 7, “Parts listing, ThinkServer RD220 Type 3729, 3779, 3797, and 3798,” on page 231 to
determine which components are customer replaceable units (CRU) and which components are field
replaceable units (FRU).
v If an action step is preceded by “(Trained service technician only),” that step must be performed only by a
trained service technician.
Power-supply LEDs
Description Action NotesAC DC Error
Off Off Off No ac power to
the server or a
problem with the
ac power source.
1. Check the ac power to the server.
2. Make sure that the power cord is
connected to a functioning power
source.
Normal condition
when no ac power is
present.
Off Off On No ac power to
the server or a
problem with the
ac power source
and the power
supply had
detected an
internal problem.
1. Replace the power supply.
2. Make sure that the power cord is
connected to a functioning power
source.
This only happens
when a second
power supply is
providing power to
the server.
Off On Off Faulty power
supply
Replace the power supply.
Off On On Faulty power
supply
Replace the power supply.
On Off Off Power supply not
fully seated,
faulty system
board, or faulty
power supply
1. Reseat the power supply.
2. If the 240V Failure LED on the system
board is lit, have the system board
replaced.
3. If the 240V Failure LED on the system
board is not lit, replace the power
supply.
Typically indicates a
power supply is not
fully seated.
On Off On Faulty power
supply
Replace the power supply.
On On Off Normal operation
On On On Power supply is
faulty but still
operational
Replace the power supply.
Server power features
When the server is connected to a power source but is not turned on, the operating
system does not run, and all core logic except for the Integrated Management
Module (IMM) is shut down; however, the server can respond to requests from the
IMM, such as a remote request to turn on the server. The power-on LED flashes to
indicate that the server is connected to power but is not turned on.
Turning on the server
Approximately 3 minutes after the server is connected to power, the power-control
button becomes active, and one or more fans might start running to provide cooling
while the server is connected to power. You can turn on the server and start the
52 ThinkServer RD220 Types 3729, 3779, 3797, and 3798: Hardware Maintenance Manual