Troubleshooting Without Diagnostics

Solving Power Supply Problems (Continued)

Problem

Cause

Solution

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.

Troubleshooting Guide

www.hp.com

2–11