HP Z220 SFF Maintenance And Service Manual page 164

Table 4-8
Activity
System does not power-on
and LEDs are not blinking.
No beeps.
The BIOS option you select controls the blue LED function during these suspend modes.
*
152 Chapter 4 Diagnostics and troubleshooting
Diagnostic lights and audible codes (continued)
Possible cause
System unable to power
on.
Recommended action
CAUTION:
Internal components might be powered even when
the computer is off. To prevent damage, disconnect the computer
power cord before you remove a component.
To resolve the problem, choose one of the following options:
Press and hold the power button for less than four seconds. If the
hard disk drive LED turns green, then:
1. Remove the expansion cards one at a time and try holding
the power button again for less than four seconds.
2.
The problem might be on the system board. Contact HP for
assistance.
Press and hold the power button for less than four seconds. If the
hard disk drive LED does not turn on green then:
1.
Check that unit is plugged into a working AC outlet.
2.
Open the access panel and check that the power button
harness is properly connected to the system board.
3. Check that all power supply cables are properly connected
to the system board.
4. Check the power supply functionality.
a. Disconnect the AC power.
b. HP Z820 Workstation only—Remove the power supply
from the chassis. All other workstations, unplug cables
connected to system board.
c. Plug in AC power.
If the power supply fan spins and the BIST LED
●
illuminates, the power supply is good; replace the
system board.
If the power supply fan does not spin or the LED
●
does not illuminate, replace the power supply.