PC Won’t Turn On? The 10 Most Common Causes & How to Check Safely

Pressed the power button and… nothing? You’re not alone. From dodgy powerboards to tired batteries, there are many simple—safe—checks you can try before booking a repair. Below we explain the likely causes, what you can test at home, and when it’s best to let a pro handle it.

TL;DR
• Start with the wall socket, powerboard, and charger ⚡
• Look for lights, fan spin, or charging indicators 🔋
• Try a safe “flea power” discharge (hold power 15–20s, no mains connected)
• If there’s a burning smell, swelling battery, liquid damage, or repeated shutdowns—stop and call a pro
• AEPC in Burswood can diagnose the fault and protect your data

The 10 most common “won’t turn on” causes

1. The wall socket or powerboard is off (or RCD tripped)
   A bumped switch or tripped RCD can cut power without you noticing—common after storms or vacuuming.

2. Damaged power cable or charger
   Frayed insulation, kinks near the plug, or a loose barrel/USB-C connection can prevent charging or power-on.

3. Battery is deeply drained or has aged out
   Laptops can refuse to boot if the battery voltage is too low or the health is poor—even when the charger is connected.

4. Power button or I/O board fault
   On many laptops the power button is a tiny separate board/cable. If it fails, the machine stays lifeless.

5. Overheating protection
   Heavy dust or blocked vents can trigger thermal protection. The system may click on for a second, then off.

6. Power surge took out the PSU (desktop) or charging circuit (laptop)
   A surge can silently kill a desktop PSU or a laptop’s charge controller.

7. Display issue (it’s on, but the screen is black)
   You might hear fans or drive noise, but the screen stays black: brightness keys, external screen, or panel/backlight faults.

8. Peripheral or USB device shorting
   Faulty USB devices, docks, or printers can prevent a normal power-on.

9. Memory or storage problems
   Systems can “power” but fail to initialise. You might see a flashing LED or hear beeps—still feels like “no power” to most users.

10. Motherboard/logic board failure
    Liquid damage, corrosion, or component failure can stop power delivery entirely.

Real-world in East Auckland:

• A Howick student’s laptop “died” before exams—turns out the third-party charger was under-powering it.

• A Pakuranga home office PC wouldn’t start after rain; the garage RCD had tripped.

• A Botany retail point-of-sale PC suffered a surge—PSU replacement and surge-protected powerboard fixed it.

Quick self-checks & tips (safe, no tools)

• Check power at the wall: Plug in a lamp/phone charger to confirm the outlet works. If you use a powerboard, try a wall socket directly.

• Inspect the charger/cable: Look for frays, burnt smells, bent pins, or wobbly connectors. If you have a genuine spare, test it.

• Battery indicator lights: On some laptops, an LED shows charging (amber/white). No light can mean charger or port trouble.

• Remove accessories: Unplug docks, USB drives, printers, and HDMI. Try powering on with only the charger connected.

• Static/flea power discharge (laptops & small desktops):

  1. Disconnect charger and all accessories.

  2. Hold the power button for 15–20 seconds.

  3. Reconnect the charger only and try again.

• External display test (if you suspect the screen): Connect to a TV/monitor via HDMI and use your display toggle key (often Fn + a function key).

• Listen & look: Any fan spin, keyboard backlight, or drive LED? Note what you see—it helps diagnosis.

Stop and call a pro immediately if:
• You smell burning or see smoke
• The battery looks swollen or the case is bulging
• There was liquid spill or a major power surge
• The device keeps power-cycling

When to call a professional

• You’ve tried the safe checks and it’s still dead.

• The charger/port feels loose or sparks.

• The laptop only powers on when the charger is held “just right.”

• There are beeps/blink codes or it shuts off a second after starting.

• You’re worried about your data—don’t keep forcing starts.

What we do at AEPC (Auckland East PC)

1. Friendly intake & questions – what happened, any spills/surges, recent updates.

2. Power & safety inspection – outlet, charger, battery health, visible damage.

3. Non-invasive diagnostics – verify power rails, LEDs, basic board checks, and screen tests (no risky teardown).

4. Clear quote – we explain the fault, parts availability (genuine/OEM), and repair options. No jargon, no pressure.

5. Parts sourcing – fast local/NZ supplier sourcing to minimise downtime.

6. Data-first approach – options to safeguard or back up data before repair where possible.

7. Post-repair testing & warranty – thorough burn-in and a parts & labour warranty.

Prevention & best practices

• Use a quality surge-protected powerboard. Auckland’s spring storms can be spiky.

• Keep vents clear. Laptops need hard, flat surfaces—no beds/couches.

• Stick to genuine or reputable chargers. Cheap chargers often under-deliver or damage ports.

• Update sensibly. Install OS/security updates, but avoid yanking power during updates.

• Travel smart. Unplug at the wall, coil cables gently, and avoid sharp bends.

• Annual check-up. A quick clean and health check can extend lifespan.

Ready to get it sorted? (Local CTA)

AEPC – Auckland East PC
📍 9/28 Torrens Road, Burswood, Auckland 2013
📞 0279-088880
📧 akleastpc@gmail.com
🕘 Mon–Fri: 9:00 AM – 5:00 PM
🕘 Sat & Sun: 9:00 AM – 4:00 PM (reservation required)

Pop into our Burswood workshop or call us for a friendly diagnosis and clear next steps.

FAQ

1) My laptop shows a charging light but won’t turn on—what now?
Try the flea-power discharge (above) and boot with the charger only, no accessories. If still no joy, the power button/IO board, battery, or mainboard may need professional checks.

2) Desktop fans spin then it shuts off—what does that mean?
Often thermal protection or a power-supply issue. Don’t keep cycling power—book a diagnostic to prevent further damage.

3) Is my data safe if the computer won’t power on?
Usually, yes—storage can survive even when the device is dead. Avoid repeated force-ons. We’ll assess data safety first.

4) Can a CMOS/RTC battery stop a PC from turning on?
Sometimes it prevents proper startup (especially older desktops). It’s a small, safe replacement—best done by a technician.

5) Water went on the keyboard—should I try to power on?
No. Unplug, don’t charge, and bring it in. Powering on wet electronics increases damage risk.

6) It died right after a Windows/macOS update—coincidence?
Updates can expose failing batteries/PSUs or corrupt boot files. We’ll verify hardware first, then repair software if needed.

7) How long does diagnosis usually take?
Most common faults are assessed the same or next business day once the device is in our workshop. We’ll keep you informed.

8) Do you repair both Windows PCs and Macs?
Yes—desktops and laptops from major brands. We follow official guidance from Microsoft, Apple, and OEMs for safe repairs.