Solving Power Supply Problems; Testing Power Supply - HP xw9400 Service And Technical Reference Manual

Table 5-3 Minor problems (continued)
Problem
Workstation does not power on
and the LEDs on the front of
the workstation are not
flashing.

Solving power supply problems

Testing power supply

Before reseating or replacing the power supply, use the BIST feature to determine if the power supply
still works.
ENWW
Cause
System unable to power on.
Possible Solution
4. Replace the processor fan.
5. Reseat CPU heatsink and verify that the fan assembly
is properly attached.
CAUTION Disconnect AC power from the
workstation before reseating or replacing
components because there is power to the system
board even when the workstation is powered down.
Press and hold the power button for less than four seconds.
If the hard drive LED turns green, then:
1. Remove the expansion cards.
2. Replace the system board.
OR
If the HDD LED does not illuminate, then:
1. Verify that the unit is plugged into a working AC outlet.
2. Open the access panel, and verify that the power
button harness is properly connected to the inline front
panel I/O device assembly connector.
3. Verify that the power supply cables are properly
connected to the system board.
4. Verify power supply functionality:
a. Disconnect AC power.
b. Remove all internal power supply cables from the
system board.
c. Plug in AC power.
●
If the power supply fan spins and the BIST*
LED lights, then the power supply is good.
Replace the system board.
●
If the power supply fan does not spin or the
BIST* LED does not light, replace the power
supply.
Troubleshooting scenarios and solutions 111