Sun Microsystems 5500, Reference Manual

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7-10 Sun Enterprise 6500/5500/4500 Systems Reference Manual • April 1998
7.4.3 Troubleshooting a PCM
A green LED is lit on the power supply when it is operational. When a PCM fails, a
yellow LED is lit on the power supply.
You will see a message similar to the following example on your system console
when a PCM fails:
See Chapter 10 “Flow Diagrams for Troubleshooting,” for more information.
7.4.4 Replacing a PCM
Caution –
Do not replace a PCM while the system is in the low power mode. Remove
and replace the PCM only in a running system. Replacing a PCM during low power
mode will cause the system to power up immediately and result in a severe overload
condition for that PCM (the other PCMs will remain in the low power mode).
The system is in the low power mode if the front panel and board LEDs are all off
while the yellow LEDs are lit on the power supplies.
Caution –
Replace the PCM within several minutes or risk overheating the board(s)
cooled by the fans in that power supply.
Remember the following rules for hot-plug replacement of a PCM:
■
The peripheral power supply must be fully operational (to provide precharge
current.)
■
There must be a redundancy of electrical power (
TABLE 7-3
) in the system.
WARNING: Core Power Supply 2 Failing
WARNING: Redundant power lost