Maintenance and Service Guide

Table Of Contents
SolutionCause
1. Be sure that the computer air vents are not blocked and the processor
cooling fan is running.
2. Open the access panel, press the power button, and see if the processor
fan (or other system fan) spins. If the fan does not spin, be sure that the
fan cable is plugged onto the system board header.
3. If the fan is plugged in and not spinning, replace it.
Processor thermal protection activated. A fan
might be blocked or not turning, or the heat sink
is not properly attached to the processor.
Power light blinks red four times followed by a two-second pause and the computer
beeps f
our times (Beeps stop after fth iteration but lights continue blinking)
Use this information to troubleshoot the computer.
SolutionCause
1. If the computer has a voltage selector, check that the voltage selector,
l
ocated on the rear of the power supply (some models), is set to the
appropriate voltage. Proper voltage setting depends on your region.
2. Open the access panel, and be sure that the power supply cable is
seated into the connector on the system board.
3. Check whether a device is causing the problem by removing all attached
devices (such as hard drives or optical drives and expansion cards). Turn
on the system. If the system enters POST, then power o and replace
one device at a time and repeat this procedure until failure occurs.
Replace the device that is causing the failure. Continue adding devices
one at a time to ensure all devices are functioning properly.
4. Replace the power supply.
5. Replace the system board.
Power failure (power supply is overloaded).
Solving hard drive problems
These tables provide common causes and solutions for hard drive problems.
Hard drive error occurs
Use this information to troubleshoot the computer.
SolutionCause
1. In Windows 10, type
file in the taskbar search box, and then select
File Explorer
from the list of applications. In the left column, expand
This PC
, right-click a drive, select Properties, and then select the Tools
tab. Under Error checking
, select Check.
2. Use a utility to locate and block usage of bad sectors. If necessary,
r
eformat the hard disk.
Hard disk has bad sectors or has failed.
Disk transaction problem
Use this information to troubleshoot the computer.
Power light blinks red four times followed by a two-second pause and the computer beeps four times (Beeps stop after f
th
iteration but lights continue blinking) 57