HP Z220 SFF Maintenance And Service Manual page 146

Table 4-6
Problem
134 Chapter 4 Diagnostics and troubleshooting
Power supply problems (continued)
Cause Solution
If the system enters the POST, perform the following:
a.
Power off the workstation.
b. Replace one device at a time and repeat this
procedure until a failure occurs.
c. Replace the device causing the failure
d.
Continue adding devices one at a time to verify
that all devices are functioning.
2. Verify power supply functionality.
a. Disconnect AC power.
b. Remove the Z820 PSU from the chassis.
c. Unplug all system board power cables for the
Z220 CMT, Z420, and Z620.
d.
Plug in AC power.
If the PSU fan spins and the LED
●
illuminates (see
on page 133), the power supply is good.
Replace the system board.
If the PSU fan does not spin or the LED
●
does not illuminate (see
supply on page
supply.
Testing power supply
Testing power
133), replace the power