🧰 Desktop & Laptop Troubleshooting + Repair 🟩 Module A – Lesson-2

🎯 Lesson Goal
  • Desktop/Laptop ki 90% common problems khud diagnose karna
  • Parts badalne se pehle sahi root cause pakadna
  • Customer ke saamne confident troubleshooting karna

🔹 Part-1: Troubleshooting Mindset (sabse zaroori)

👉 Golden Rule:
“Part change nahi, pehle fault confirm”

Troubleshooting Flow:
  1. Problem poocho (kab se, kaise, last change kya tha?)
  2. Visual check (burn, loose cable, dust, liquid)
  3. Basic test (power, display, beep, fan)
  4. Isolation (RAM, HDD, battery, charger)
  5. Confirm → Fix → Test

🔹 Part-2: Desktop Common Problems (Practical)
❌ Problem 1: PC ON nahi ho raha
  1. Check order (Step-by-Step):
  2. Power cable, switch, socket
  3. PSU switch (ON?)
  4. 24-pin + 8-pin CPU cable
  5. Front panel power button (short test screwdriver se)
  6. CMOS reset (battery nikalo 5 min)
  7. PSU test (multimeter / spare PSU)
✅ Conclusion:
  • PSU dead → replace
  • Motherboard dead → confirm with spare PSU
❌ Problem 2: ON hota hai, Display nahi
Steps:
  1. Monitor + cable test
  2. GPU reseat / remove → motherboard display try
  3. RAM remove → clean → single stick test
  4. Beep code suno
  5. CMOS reset

📌 Real tip:
70% cases mein RAM dust issue hota hai

❌ Problem 3: Baar-baar Restart / Hang
Steps:
  • CPU temp check
  • Thermal paste reapply
  • HHD SMART check
  • RAM test (MemTest)

🔹 Part-3: Laptop Troubleshooting (Most Important)

❌ Laptop ON nahi ho raha
Flow:

  • Charger LED ON?
  • Adapter voltage check (multimeter)
  • Battery remove → direct power test
  • Power button long press (30 sec)
  • RAM reseat
  • CMOS reset (internal battery)

❌ Laptop ON but Display nahi
Steps:
  1. External monitor connect
  2. RAM reseat
  3. BIOS blind reset
  4. Screen cable loose?
  5. GPU chipset fault (common in old HP/Dell)
❌ Laptop Charging but Battery not charging
  • Battery health check
  • BIOS update
  • Charger watt mismatch
  • Battery replacement

🔹 Part-4: Laptop Parts Replacement (Hands-On)
🔧 RAM Replacement
  • Same DDR & speed
  • Single stick test first
🔧 HDD → SSD Upgrade
  1. Old HDD nikaalo
  2. SSD lagao
  3. Fresh Windows install
  4. Old data copy

📌 Customer Script:
“SSD upgrade se laptop 3x fast ho jaayega”

🔧 Keyboard Replacement

  • Back screws open
  • Ribbon cable unlock carefully
  • Test before full screw tight

🔧 Screen Replacement

  • Model number exact match
  • 30-pin / 40-pin confirm
  • Screen test before final fit

🔹 Part-5: Software Troubleshooting (Daily Work)

Windows Slow / Virus

  • Startup disable
  • Malware scan
  • Fresh Windows (best solution)

Blue Screen (BSOD)

  • RAM test
  • Driver update
  • Windows reinstall

🔹 Part-6: Tools Every Technician Must Have

  • Screwdriver kit
  • Multimeter
  • Bootable USB (Windows + Linux)
  • Thermal paste
  • Cleaning blower
  • LAN tester
🧪 Practical Assignment (Must Do)

✅ Task-1:
Ek desktop kholo → RAM nikalo → clean → boot test
✅ Task-2:
Kisi laptop mei HDD nikal kar SSD lagao (agar possible)
✅ Task-3:
Charger voltage multimeter se measure karo
📋 Checklist (Lesson-2 Pass)
✔ Desktop no-display fix
✔ Laptop power diagnosis
✔ HDD → SSD upgrade
✔ Thermal paste apply correctly

🧠 Technician Confidence Tip
“Customer ko fault samjhao, darao nahi – bharosa banao”