HP Z440 Workstation Series Maintenance And Service Manual page 99

Problem
every second), followed by a two-
second pause.
Power LED flashes red (once every 2
seconds).
Cause
A fan might be blocked or not
turning.
OR
The processor heatsink fan
assembly is not properly
attached to the processor.
Power failure (power supply is
overloaded).
Solution
2. Open the access panel and press the workstation power
button.
3. Verify that the system fan is running.
4. Verify that the processor heatsink fan spins.
If the heatsink fan is not spinning, verify that the fan
cable is plugged into the system board connector. Verify
that the fan is properly seated.
5. Replace the processor heatsink.
1. Determine whether a device is causing the problem by
performing the following:
a. Disconnect AC power.
b. Remove all attached devices.
c. Power on the workstation.
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 Z840 PSU from the chassis.
c. Unplug all system board power cables for the
Z440 and Z640.
d. Plug in AC power.
●
If the PSU fan spins and the LED illuminates
(see Testing power supply on page
power supply is good. Replace the system
board.
●
If the PSU fan does not spin or the LED does
not illuminate (see
on page 88), replace the power supply.
Troubleshooting scenarios and solutions
88), the
Testing power supply
89