IBM System x3550 M4 Installation And Service Manual page 39

Figure 13. DC power supply LEDs
v Ethernet activity LEDs: When these LEDs are lit, they indicate that the server is
transmitting to or receiving signals from the Ethernet LAN that is connected to
the Ethernet port.
v Ethernet link LEDs: When these LEDs are lit, they indicate that there is an
active link connection on the 10BASE-T, 100BASE-TX, or 1000BASE-TX interface
for the Ethernet port.
v AC power LED: Each hot-swap ac power supply has an ac power LED. When
the ac power LED is lit, it indicates that sufficient power is coming into the
power supply through the power cord. During typical operation, the ac power
LED is lit. For any other combination of LEDs, see "AC power-supply LEDs" on
page 142.
v DC power LED: Each hot-swap ac power supply has a dc power LED. When
the dc power LED is lit, it indicates that the power supply is supplying adequate
dc power to the system. During typical operation, both the ac and dc power
LEDs are lit. For any other combination of LEDs, see "AC power-supply LEDs"
on page 142.
v IN OK power LED: Each hot-swap dc power supply has an IN OK power LED.
When the IN OK power LED is lit, it indicates that sufficient power is coming
into the power supply through the power cord. During typical operation, both
the IN OK and OUT OK power LEDs are lit. For any other combination of
LEDs, see "DC power-supply LEDs" on page 143.
v OUT OK power LED: Each hot-swap dc power supply has an OUT OK power
LED. When the OUT OK power LED is lit, it indicates that the power supply is
supplying adequate dc power to the system. During typical operation, both the
IN OK and OUT OK power LEDs are lit. For any other combination of LEDs,
see "DC power-supply LEDs" on page 143.
v Power-supply error LED: When the power-supply error LED is lit, it indicates
that the power supply has failed.
Note: Power supply 1 is the default/primary power supply. If power supply 1
fails, you must replace the power supply immediately.
v Power-on LED: When this LED is lit and not flashing, it indicates that the server
is turned on. The states of the power-on LED are as follows:
Off: Power is not present, or the power supply or the LED itself has failed.
Flashing rapidly (4 times per second): The server is turned off and is not
ready to be turned on. The power-control button is disabled. This will last
approximately 5 to 10 seconds.
Chapter 1. The IBM System x3550 M4 server
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