CompTIA Certifications

A+ Certification: Part 3 – Hardware: Upgrades, Troubleshooting and Preventative Maintenance

Section Objectives

After you complete this section you will:

Understand the troubleshooting process.

Understand what POST is.

Understand the different POST error codes.

Troubleshooting Issues and Problems

As an IT support person, you will need to work with customers throughout your career. Most often, you will hear from your customers when something isn’t working for them, and often times, they can be irate. As we used to say, “They never call the cable company when it’s working.”

Providing good customer service is extremely important in building a good relationship with your customers. Unfortunately, your troubleshooting job requires getting information from the customer who may not be in the frame of mind to provide it.

What problem are you experiencing?

First, you need to determine the user’s problem in their own words. Though you may know it is not as they are explaining it, allowing the customer to explain the problem will help in the process of solving and calming them down.

One of the principles I learned in support was that the user was never at fault. Most often, the problem occurred because of some action taken by the user, though when you are discussing the issue with them, you need to keep the mindset that it is not their fault. This helps prevent their egos from being hurt because of something they may have done.

My first job in IT support provided a great deal of experience and taught me a lot about support. On my first day of work there, I arrived a few minutes early. An employee in a different department came over and found me and told me she had a problem. I was, of course, gung ho about solving my first issue. She explained that her laptop would not turn on. I proceeded to plug the power supply in for her. She was so embarrassed, I explained that it happens all the time and not to worry!

Is it software or hardware related?

After you determine the user’s problem and ask some questions to understand it, determine at this point if it is a hardware or software issue. If it is a hardware issue, you will either need to send a tech or look at it yourself. If it is a software issue, many of these can be handled over the phone.

Determine More Information

Find out if the user has experienced any error codes, beeps at bootup, or anything unusual. This can help in your troubleshooting when you have the equipment.

Also find out any symptoms the user may have been experiencing, or even more valuable, anything the user was doing when the computer started malfunctioning.

I once received a help desk ticket for a vice president who’s laptop stopped functioning. I picked it up from him to find out what the problem was. The computer would not turn on. I started removing components and coffee started dripped from the battery slot and hard drive. I called him and he explained that he “spilled a cup of coffee into the laptop and it stopped working then and he forgot to tell me.”


POST, or Power On Self Test is your first source of troubleshooting a problem. POST automatically runs when your computer is turned on and tests several components of your PC.

The Processor – if the test fails for the CPU, the system stops usually with no error code.

ROMs – POST checks the BIOS ROMs. If there is a problem, the system will stop, usually with no error code.

DMA Controller – if there are any problems with the DMA controller, the system will stop.

Interrupt Controller – if POST detects problems with the Interrupt Controller the system will give an audible error signal of one long beep then one short beep then the system stops.

System Timing Chip – this chip provides timing signals for the bus and processor. Any errors will produce an audible error signal of one long beep and one short beep then the system stops.

Video Card – if the Video Card fails, there will be one long beep then two short beeps then the system halts.

RAM – any RAM errors will generate a “201: Memory Error” message on the screen. Any error codes beginning with 2 indicate a memory error.

Keyboard – a problem with the keyboard will result in a “301: Keyboard Failure” error message followed by a short beep. System may halt or may ignore the error.

Floppy Drives – any problems will result i
n a “601: Floppy Disk” error code appearing on the screen.

Other Devices – POST checks the other ports and components of the computer, beeps, then continues. It also checks the Master Boot Record (MBR) on the hard drive. If it cannot find the MBR, it will freeze and not continue loading, otherwise it hands control over to the MBR (or DOS Boot Record (DBR) if it is booting from a floppy).

Summary of POST error codes:

Error Code Problem Description
1xx System Board problem
161 CMOS Battery Failure
164 Memory System Size error
2xx Memory related problem
3xx Keyboard problem
4xx Monochrome video problem
5xx Color video problems
6xx Floppy Disk problem
17xx Hard disk problem

After studying this section you should:

Understand the troubleshooting process.

Identify the problem with your customer. Is it hardware or software? Are they experiencing any error codes or indications? What were they doing when the problem started occuring?

Understand what POST is.

POST, or Power On Self Test is the test the computer runs when you power it on. It checks components and peripherals for problems and reports a problem using beeps or an error message.

> Understand the different POST error codes.