Service manual

2-12 AlphaServer DS20 Service Manual
2.7 Troubleshooting with LEDs
During power-up, reset, initialization, or testing, diagnostics are run on CPUs,
memories, P-chips, and the PCI backplane and its embedded options. Although
system LEDs are not visible when the side panels are on, they can be viewed when
the card cage side of the system is exposed and the top cover is on. There are
LEDs on the CPU and server feature modules.
Figure 2-2 CPU and Server Feature Module LEDs
Sys Fan OK
CPU Fan O
K
Temp OK
PK1407-99
5 Vaux
Power OK
5V OK
2V OK
SROM Clk
CPU DC OK
CPU Self-test
CPU
Module
Server
Feature
Module