Service manual

Troubleshooting 3-75
CPU LED – If the Run LED is off when it should be on, the CPU could be
broken.
H-switch power manager LEDs – If the DC OK LED is off, the onboard +5V
and/or +3V regulator is broken. If the Reset/Initialize LED is on, the module is
in the reset state and may not have passed self-test.
H-switch power supply LEDs – If the Vaux LED is off, check that Vaux is
OK at other system locations. If it is, Vaux is not present at the power supply
for some reason or the power supply is broken. If any of the other LEDs are off
with the exception of the Swap OK LED, the power supply is broken.
Master clock LED – If the master clock LED is off, the master clock is not
working properly. The entire system is affected, and the system will not power
up. The console reports a GR_CLK_OK_TIMEOUT.
Console serial bus ID LEDs – If the SCM master LED is on, the SCM in this
PCI is master of the CSB bus. If it is off and there is only one standard I/O
module in the system, then there is something wrong with the standard I/O
module or the PCI in which it sits.
If the PBM built-in self-test LED is on, either the PBM is performing self-test or
it did not pass self-test. Since the PBM micro is on the PCI backplane, the
backplane could be broken or the PBM firmware could be corrupt.
If the SCM built-in self-test LED is on, either the SCM is performing self-test or
it did not pass self-test. Since the SCM micro is on the standard I/O module,
that module could be broken or the SCM firmware could be corrupt.
If the PCI DC power LED is off, there is a problem with power to the PCI.
If the Vaux present LED is off, there is a problem with power to the PCI or the
Vaux signal is not reaching the CSB bus ID module. See Section 3.1.
Swap OK LEDs – All Swap OK LEDs are powered by the PSM +5V hot swap
converter. When lit, they indicate that the logic voltages are not present at the
modules. If the +5V converter is functioning even if the PSM is broken in some
other way, the Swap OK LEDs will light.