Sun Microsystems Enterprise 250 Owner's Manual page 275

3. If you see no front panel LED activity, a power supply may be defective.
See "Power Supply LEDs" on page 245.
4. If the general fault LED (
message, then POST has failed.
The most probable cause for this type of failure is the main logic board. However,
before replacing the main logic board you should:
a. Remove optional PCI cards.
b. Remove optional DIMMs.
Leave only the four DIMMs in Bank A.
c. Repeat POST to determine if any of these modules caused the failure.
d. If POST still fails, then replace the main logic board.
Video Output Failure
Symptom
No video at the system monitor.
Action
1. Check that the power cord is connected to the monitor and to the wall outlet.
2. Verify with a volt-ohmmeter that the wall outlet is supplying AC power.
3. Verify that the video cable connection is secure between the monitor and the
video output port.
Use a volt-ohmmeter to perform the continuity test on the video cable.
4. If the cables and their connections are okay, then troubleshoot the monitor and
the graphics card.
) remains lit, or the POST output contains an error
Chapter 11 Diagnostics and Troubleshooting 257