Chapter 5: Hardware & Network Troubleshooting 

5.1 Troubleshooting Methodology (MEMORIZE EXACT ORDER)

This is one of the most tested objectives.

The 6-Step Process

1. Identify the problem
   2. Establish a theory of probable cause
   3. Test the theory
   4. Establish a plan of action and implement solution
   5. Verify full system functionality
   6. Document findings

Key Notes:

• Always start with user questions
• Do NOT skip steps on the exam
• Documentation is always last

 5.2 Safety Procedures

Electrical Safety

• Disconnect power before opening devices
• Use proper grounding

ESD Protection (Electrostatic Discharge)

• Use anti-static wrist strap
• Work on non-conductive surfaces

Environmental Safety

• Avoid liquids near devices
• Ensure proper ventilation

5.3 Common Hardware Problems

No Power

Symptoms:

• No lights
• No fan movement

Causes:

• Dead PSU
• Loose cables
• Faulty outlet

Solutions:

• Check power cable
• Test outlet
• Replace PSU

No POST (Power-On Self-Test)

Symptoms:

• System powers on but no display
• Beep codes

Causes:

• RAM failure
• CPU issue
• Motherboard failure

Solutions:

• Reseat RAM
• Test components
• Replace faulty hardware

 No Display

Causes:

• Monitor off
• Loose cable
• GPU failure

Fix:

• Check connections
• Try different monitor
• Reseat GPU

 Beep Codes

• Indicate hardware failure
• Vary by BIOS manufacturer

Common Meanings:

• Continuous beeps → RAM issue
• No beep → possible motherboard failure

Overheating

Causes:

• Dust buildup
• Fan failure
• Poor airflow

Fix:

• Clean system
• Replace fan
• Apply thermal paste

 Slow Performance

Causes:

• Low RAM
• HDD instead of SSD
• Too many background processes

Fix:

• Upgrade RAM
• Install SSD
• Close programs

5.4 Storage Troubleshooting

Drive Not Detected

Causes:

• Loose cable
• BIOS disabled
• Dead drive

Fix:

• Check SATA/power
• Enable in BIOS
• Replace drive

Slow Disk Performance

Causes:

• Fragmentation (HDD)
• Failing drive

Fix:

• Defragment (HDD only)
• Replace with SSD

Clicking Noise (HDD)

• Mechanical failure
• Immediate backup required

5.5 Network Troubleshooting

No Network Connection

Causes:

• Disabled adapter
• Bad cable
• Wrong settings

Fix:

• Enable NIC
• Replace cable
• Check IP settings

No Internet Access

Causes:

• DNS failure
• Gateway issue
• ISP outage

Fix:

• Use ipconfig
• Ping gateway
• Check DNS

Weak Wi-Fi Signal

Causes:

• Distance
• Interference
• Obstacles

Fix:

• Move closer
• Change channel
• Use extender

Slow Network

Causes:

• Bandwidth congestion
• Old router

Fix:

• Switch to 5 GHz
• Upgrade router

5.6 Command-Line Tools (EXAM CRITICAL)

Essential Commands

ipconfig      → View IP settings
ping          → Test connectivity
tracert       → Trace route
nslookup      → DNS lookup
netstat       → Active connections

Example Workflow:

1. Run ipconfig → Check IP
2. Run ping 127.0.0.1 → Test local stack
3. Ping gateway → Check local network
4. Ping external → Check internet

 5.7 Wireless Troubleshooting

Common Issues:

Cannot Connect to Wi-Fi

• Wrong password
• SSID hidden

 Interference Sources:

• Microwaves
• Bluetooth devices
• Other networks

Fix:

• Restart router
• Change channel
• Forget/reconnect network

5.8 Printer Troubleshooting

Common Issues:

Paper Jam

• Remove jam carefully

No Print Output

• Check ink/toner
• Restart printer

Printer Offline

• Check connection
• Restart spooler

5.9 Mobile Device Troubleshooting

Issues:

Battery Drain

• Background apps
• Old battery

 No Connectivity

• Airplane mode
• Network settings

Frozen Screen

• Restart device

5.10 Troubleshooting Scenarios (PBQ STYLE)

Scenario 1:

PC powers on but no display
Likely: GPU or RAM

Scenario 2:

Connected to Wi-Fi but no internet
Likely: DNS or gateway

Scenario 3:

Laptop shuts down randomly
Likely: overheating

Scenario 4:

Slow PC with HDD
Upgrade to SSD

5.11 Preventive Maintenance

Hardware:

• Clean dust regularly
• Check fans

Software:

• Update OS
• Scan for malware

 Security:

• Use antivirus
• Apply updates

5.12 Exam Tips (CRITICAL)

✔ Always follow 6-step troubleshooting process
✔ Memorize command-line tools
✔ Focus on symptom → cause → solution
✔ Think like a technician, not just memorize
✔ Watch for trick answers skipping steps

Quick Knowledge Check

1. First troubleshooting step?
   A. Test theory
   B. Identify problem
   C. Replace hardware
   D. Document

2. Command to test connectivity?
   A. ipconfig
   B. ping
   C. netstat
   D. format

3. Clicking HDD noise means?
   A. Normal
   B. Virus
   C. Hardware failure
   D. Power issue

4. Weak Wi-Fi cause?
   A. RAM
   B. Distance
   C. CPU
   D. BIOS

5. No POST likely issue?
   A. Printer
   B. RAM
   C. Mouse
   D. Monitor

Answers: 1-B, 2-B, 3-C, 4-B, 5-B