Compaq AlphaServer DS20, Руководство по обслуживанию

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Troubleshooting 2-13
To see LEDs, the card cage side of the system must be exposed; the system top should
be on, and the system must be on.
CPU LEDs
The CPU LEDs are on the under side of the module. Figure 2-2 shows the location of
the LEDs when looking up at the module. Normally all CPU LEDs are on except the
SROM Clock LED.
Replace the CPU if the 5V OK LED is on and any of the following LEDs are off: CPU
DC OK, or 2V OK.
If the 5V OK LED is off, power is not getting to the CPU. The problem could be the
power harness, the power translation board, the power supply, or the CPU.
If the CPU self-test LED is off, the built-in self-test on the CPU chip did not complete
for some reason.
Server Feature Module LEDs
All the LEDs on this module are normally on.
If the 5 Vaux Power OK LED is off, power is not getting to the module and the
problem could be the power harness, the power translation board, the power supply, or
the server feature module.
If the Sys Fan OK LED is off, a system fan is broken. Use the show power command
to determine which.
If the CPU Fan OK LED is off, a CPU fan is broken. Use the show power command
to determine which.
If the Temp OK LED is off, the temperature in the cabinet is above the temperature
threshold. Several things can cause this condition: blocked airflow, temperature in the
room where the system is located is too high, the system card cage is open and air is
not channeled properly over the system. Fix any of these conditions, if possible. The
overtemperature threshold is programmable and is controlled by the environment
variable over_temp. Its default is 55 degrees C. After the system has cooled down
and can be powered up, you can change the threshold. If you do this and the
temperature inside the system gets too hot, it is likely that system errors will occur and
the system may crash. If the system gets too hot, hardware can be damaged.