Troubleshooting Guide

Troubleshooting Guide www.hp.com 2–11
Troubleshooting Without Diagnostics
Computer powered off
automatically and the
Power LED flashes Red two
times, once every second,
followed by a two-second
pause. The Power LED will
continue flashing until the
problem is resolved.
Processor thermal
protection activated:
A fan may be blocked
or not turning.
OR
The heatsink is not
properly attached to the
processor.
1. Ensure that the computer air
vents are not blocked and the
processor cooling fan is
running. Leave a 4-inch
(10.2-cm) clearance at the back
of the system unit and above the
monitor to permit the required
airflow.
2. Reboot the system and observe
if there are any POST messages
stating that one or more of the
fans are not detected. If a fan is
not detected during POST,
unplug the unit, open the chassis
and ensure that the all the fans
are plugged in correctly.
3. If fan is plugged in and seated
properly, and the POST
message still appears, then
replace the processor fan.
4. Reseat processor heatsink and
verify that the fan assembly is
properly attached. See the
appropriate Service Reference
Guide for instructions on how to
reinstall the heatsink. Correct
heatsink installation is critical to
proper system operation.
5. Contact an authorized reseller
or service provider.
Solving Power Supply Problems (Continued)
Problem Cause Solution