Troubleshooting Guide

A–18 www.hp.com Troubleshooting Guide
POST Error Messages
System does not
power on and LEDs
are not flashing.
None System unable to
power on.
Press and hold the power button for less
than 4 seconds. If the hard drive LED
turns green, then:
1. Check that the voltage selector,
located on the rear of the power
supply, is set to the appropriate
voltage. Proper voltage setting
depends on your region.
2. Remove the expansion cards one at
a time until the 3V_aux light on the
system board turns on.
3. Replace the system board.
OR
Press and hold the power button for less
than 4 seconds. If the hard drive LED
does not turn on green then:
1. Check that the unit is plugged into
a working AC outlet.
2. Open hood and check that the
power button harness is properly
connected to the system board.
3. Check that both power supply
cables are properly connected to
the system board.
4. Check to see if the 3V_aux light on
the system board is turned on. If it
is turned on, then replace the
power button harness.
5. If the 3V_aux light on the system
board is not turned on, then
replace the power supply.
6. Replace the system board.
Diagnostic Front Panel LEDs and Audible Codes (Continued)
Activity Beeps Possible Cause Recommended Action