HP COMPAQ DC5750 - Manual (Page 171)

Service Reference Guide, dc5750 437963-001 D–5
Troubleshooting Without Diagnostics
Solving Power Supply Problems
Solving Power Supply Problems
Problem Cause Solution
Power supply shuts down
intermittently.
Voltage selector switch
on rear of computer
chassis (some models) is
not switched to correct
line voltage (115V or
230V).
Select the proper AC voltage using
the selector switch.
Power supply will not
turn on because of
internal power supply
fault.
Replace the power supply.
Computer powered off
automatically and the
Power LED flashes Red two
times, once every second,
followed by a two second
pause, and the computer
beeps two times. Beeps
continue for five iterations
after which the LED flashes
will continue until the
problem is resolved.
Processor thermal
protection activated:
A fan may be blocked
or not turning.
OR
The heatsink/fan
assembly is not properly
attached to the
processor.
1. Ensure that the computer air
vents are not blocked and the
cooling fan is running.
2. Open hood, press the power
button, and see if the processor
fan spins. If the processor fan is
not spinning, make sure the
fan's cable is plugged onto the
system board header.
3. If the fan is pugged in and
seated but not spinning, replace
the processor fan.