Member Avatar for fredjahed

Hi,

I shutdown my laptop successfully last night, and today when I started, it display a message about the heat and asked me whether I want to continue. I immediately turned if off and opend it up to see if perhaps dust had acumiliated in the fan area. I didn't see major dust but I cleaned it a little anyway. After putting everything back together, when I start it, the system's light goes on, the fan starts but stops after about 10-15 seconds and there is nothing on the screen either. I checked out all connections to see if I missed something while putting things back - and I didn't see anything.

Please help.

Thanks,
Fred

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  • Latest Post Latest Post by fredjahed

Dani AI

Generated

Concise next-step checklist and focused diagnostics that build on 's question about disassembly and 's fan-seating suggestion. These steps are ordered to isolate power/POST, memory, display, and thermal-sensor failures without repeating the symptom narrative already in the thread.

Start with power/EC reset and adapter checks:

  • Remove battery and AC, then hold the power button ~30 seconds to drain residual charge. Reconnect AC only and try to power.
  • Verify the AC adapter output with a multimeter or swap in a known-good adapter. Inspect the DC jack for wobble or burn marks.

Minimal hardware POST isolation:

  • Strip to a minimal configuration: CPU/heatsink, one RAM module, no HDD/optical/card. Try each RAM stick in each slot, one at a time.
  • If no display, remove all RAM briefly and listen for POST beeps or watch for caps/num-lock LED blink patterns; those are diagnostic signals on many laptops. Clean RAM contacts with isopropyl if tarnished.

Display vs motherboard check:

  • Attach an external monitor (VGA) to distinguish LCD/inverter/backlight faults from a failed POST.
  • Shine a bright light at the LCD at power-on to check for a faint image (backlight failure). If external shows video but internal does not, focus on inverter/LCD connections.

Fan/thermal-sensor and board inspection:

  • Confirm the fan cable is seated and the fan receives voltage (multimeter) before replacing it. Many systems will power down rapidly if the EC detects no tach signal.
  • Visually inspect the motherboard for bulging/leaking capacitors or burnt components; damaged power circuitry often causes the symptoms described. Use ESD precautions and avoid running the machine with heatsink removed.

If these checks fail to produce POST or display, the fault is likely on the mainboard/embedded controller or power subsystem and merits professional diagnosis or a replacement board.

Recommended Answers

All 6 Replies

Member Avatar for disophisis

To what extent did you disassemble the laptop... did you have the memory out and all that? or did you just have the case opened.

Member Avatar for fredjahed

Yes, I took the memory sim out while I was trying to figure out how to get to the fan (which later I found out through the keyboard is the way), but I placed back the memory and it seems to be sitting correctly.

Member Avatar for Supernatural

If its turning off it sounds like a problem with the CPU cooling. Make sure to check the Fan seating I get this problem alot so make sure its pushed in correctly otherwise the CPU will keep overheating of course :) hope this helps

Member Avatar for fredjahed

If the fan is not sitting correctly, it shouldn't start...right? ...but it does for very short time and it goes off and stays off while the system LCD stays on.

Member Avatar for Supernatural

Oh.. if the fan isnt seated correctly it will start but the CPU generates too much heat and automatically shuts the PC down to try and prevent damage.

Member Avatar for fredjahed

What I meant was that the fan starts for about few seconds and then stops while the system light is on still.

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