D Troubleshooting Without Diagnostics - HP Evo D500 Reference Manual

Solving Minor Problems (Continued)
Problem
Computer powered off
automatically and the
Power LED flashes Red
two times, once every
second, followed by a
two second pause.
System does not power
on and the LEDs on the
front of the computer
are not flashing.
Service Reference Guide, d500
Cause
Processor thermal
protection activated:
A fan may be blocked or
not turning.
OR
The heatsink is not
properly attached to the
processor.
System unable to power
on.
336492-005
Troubleshooting Without Diagnostics
Possible Solution
1. Ensure computer air vents are not
blocked and the cooling fan is
running.
2. Open hood, press power button,
and see if the processor fan
spins. If not spinning, make sure
the fan's cable is plugged onto
the system board header. Ensure
the fan is fully/properly seated or
installed.
3. Replace the processor fan.
4. Reseat processor heatsink and
verify that the fan assembly is
properly attached.
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 is
set to the appropriate voltage.
2. Remove the expansion cards one
at a time until the 3.3 V_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. If the 3.3 V_aux light on the
system board is on, then replace
the power button harness.
5. If the 3.3 V_aux light on the
system board is off, then replace
the power supply.
6. Replace the system board.
D–3