I have Acer Aspire 5745G Laptop its fan started making noise. So i followed up this tutorial. And cleaned Fan and put everything back up.

But now when connecting battery automatically starts up laptop and it auto shutdown in 1-3 seconds. Pressing power button doesn't do anything.

Here how i put it back on.

On first attempt i put everything back except DVD ROM

On Second attempt i didn't connect my HDD

On third attempt i just connected basic things.(see pictures)

Cpu fan Dc charger port Video cable(Laptop screen) Webcam Power button TouchPad Dvd Rom eject button

Motherboard with fan connection only

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Screen & webcam wire connected

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Power, DVD Eject button , touchpad wire connected

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And finally connected DC Power jack wire and wifi anntena

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I didn't remove RAM & bios battery.

In third attempt laptop didn't started automatically when connecting battery. But power button still not works.

  • There's not enough information and this will most likely be closed. What model laptop? What were the steps you took? etc. – Xavierjazz Mar 4 '16 at 18:01
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    Using only your link as a reference, This system requires a lot of teardown to get to the fan... I would check the memory modules are seated properly first, then the remaining connections paying particular attention to the keyboard connections and top frame (where the power button is located). – acejavelin Mar 4 '16 at 18:02
  • @acejavelin i didn't removed ram. – Skyyy Mar 4 '16 at 18:35
  • does fan spin now? if not it will be shut down by thermoprotection. On last image white wire to your wifi seems to be touching chassis. try w/o it. Check voltage on DC jack if you have tools to see if power is supplied to mobo. – Boris G Mar 4 '16 at 18:57
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    @fixer1234 thanx... i have seprated q&A – Skyyy Mar 5 '16 at 22:13

You best option is to start again. Your laptop is hopefully detecting something is wrong and shutting down as a safety measure. It could be as simple as your CPU fan is not connected. I doubt after 3 seconds you're reaching a shutdown temperature, which could be the other option.

Most likely if you've forget to reconnect something, or something is connected the wrong way around, but check your CPU cooler and fan carefully.

Good luck.

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  • I checked fan is connected fine. updated question with more details. On third attempt my laptop didn't auto started. – Skyyy Mar 4 '16 at 18:36
  • I can't see from the photos, but double check you've got all the white connectors the right way around and that they are pushed home fully. The inserts can get pushed back sometimes, so make sure these are still in the plugs properly - i.e.: Check each wire on those white connectors to make sure the metal tags are in fully and the socket itself is in fully. – Tony68000 Mar 4 '16 at 18:47
  • Really the same goes for those ribbon connectors. Pull the white lock bar back, push in the ribbon then push the locking bar back in place. Sorry if these are obvious instructions but just trying to think of everything. – Tony68000 Mar 4 '16 at 18:51
  • Another try - ensure the fan can move (by hand). If it can't, because a wire is trapped, then the cpu could shutdown as a safety measure. – Tony68000 Mar 4 '16 at 18:53
  • Fan is not trapped its easily movable by hand. Which ribbon connectors are you talking about? – Skyyy Mar 4 '16 at 18:57

Found the issue. Power button wire connection pin was damaged and it was causing short circuit making laptop automatically start and shutdown.

Cable damaged pins

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