CompTIA A+

CompTIA A+ domain 5: Hardware & network troubleshooting — What you need to know for the exam

June 25, 2022 by Greg Belding

The CompTIA+ certification is one of the best certifications for those in help desk support or desktop support who want to verify their skills to employers. As many know, the lifeblood of this area of IT is troubleshooting hardware and network issues.  

This article will detail domain 5, hardware and network troubleshooting, and will explore the material this domain covers. We will cover how to apply the best practice methodology to resolve problems and troubleshoot problems related to motherboards/RAM/CPU/power, storage drives and RAID arrays, video issues, mobile devices, printer issues, and wired/wireless networks. 

Domain 5: Hardware and network troubleshooting

As mentioned above, hardware and network troubleshooting is the cornerstone of help desk and desktop support. It has therefore become the largest of all domains on the CompTIA+ Core 1 certification exam. A+ certification candidates must pass the A+ Core 1 and Core 2 exams to earn this cert. This domain accounts for 29% of exam material covered by the A+ Core 1 exam. To put it into perspective, it makes up nearly three times as much material as the smallest domain of knowledge! Below are the domains of knowledge covered by the A+ Core 1 certification exam:

  • 1.0  Mobile devices
  • 2.0  Networking
  • 3.0  Hardware
  • 4.0  Virtualization and cloud computing
  • 5.0  Hardware and network troubleshooting

What’s new in domain 5: Hardware and network troubleshooting?

The more appropriate question is, “What has been removed”? This domain has not changed much since the last exam update. What has changed on the A+ exam is that several of the objectives covered by the subdomains have been removed and most objectives have changed for some subdomains. For example, in subdomain 5.7 (which we will explore later in the article), this latest exam update has removed the objectives of IP conflict, low RF signal, and SSID not found. No explanation has been given for this removal of content, but it does fit into the general trend of consolidation and updating of exam material observed in other domains of the A+ Core 1 certification exam.

Aside from this, the changes made since the last exam update don’t warrant a side-by-side comparison of the subdomains. With that said, let’s delve into the subdomains covered by domain 5.

Domain 5: Hardware and network troubleshooting exam outline

Below is the exam outline for domain 5 of the A+ Core 1 certification exam.

5.1 Given a scenario, use the best practice methodology to resolve problems

This subdomain covers best practices related to problem-solving for help desk and desktop support roles. Please note that these best practices are prefaced with the suggestion that you always consider corporate policies, procedures, and impacts before implementing changes. This approach gives these best practices the flexibility to bend to your organization’s needs when necessary.

Best practices:

  1.     Identify the problem
  2.     Establish a theory of probable cause (question the obvious)
  3.     Test the theory to determine the cause
  4.     Establish a plan of action to resolve the problem and implement the solution
  5.     Verify full system functionality and, if applicable, implement preventive measures
  6.     Document findings, actions, and outcomes

5.2 Given a scenario, troubleshoot problems related to motherboards, RAM, CPUs, and power

The only overarching concept in this subdomain is that of common symptoms. The common symptoms of the problems related to motherboards, RAM, CPUs, and power cover 12 items. They range from power-on self-test beeps (POST), overheating, grinding noise and continuous reboots to application crashes, burning smell, capacitor swelling, and inaccurate system date/time. 

5.3 Given a scenario, troubleshoot and diagnose hard drives and RAID arrays

Common symptoms is the only concept covered by this subdomain, which covers ten items related to hard drive and RAID array troubleshooting. These items range from grinding noises, clicking noises and RAID failure to missing drives in OS, and self-monitoring, analysis, and reporting technology (S.M.A.R.T.) failure. 

5.4 Given a scenario, troubleshoot video, projector, and display issues

The only concept here is common symptoms (see a trend?). These common symptoms range from incorrect data source, dead pixels, and fuzzy images to display burn-in and intermittent projector shutdown. 

5.5 Given a scenario, troubleshoot common issues with mobile devices

This subdomain’s only concept is also common symptoms. The common symptoms cover 11 items ranging from poor battery health, swollen battery, improper charging and overheating to physically damaged ports, malware, and cursor drift/touch calibration. 

5.6 Given a scenario, troubleshoot and resolve printer issues

Some consider printers the bane of help desk and desktop support. If you are in this camp, this subdomain may be useful on your job. The common symptoms in this subdomain cover 16 items ranging from lines down the printed page, paper jams, faded print, and paper not feeding to speckling on printed pages, incorrect color settings, and incorrect page orientation. 

5.7 Given a scenario, troubleshoot problems with wired and wireless networks

Common symptoms of this subdomain cover eight items. These items range from intermittent wireless connectivity, slow network speeds, limited connectivity and jitter to port flapping, high latency, and external interference. 


Since the early days of help desk and desktop support, the bread and butter of the support tech’s work has been hardware and network troubleshooting. Today it is the weightiest of the domains on the CompTIA A+ certification exam. Are you interested in learning more about this domain and the others covered by the CompTIA A+ certification exam? If so, you should explore the Infosec CompTIA A+ certification hub. 


Posted: June 25, 2022
Greg Belding
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Greg is a Veteran IT Professional working in the Healthcare field. He enjoys Information Security, creating Information Defensive Strategy, and writing – both as a Cybersecurity Blogger as well as for fun.