In this post I’ll explain how to troubleshoot a dead laptop and find the problem. The following troubleshooting tips are not model and brand specific, they should work for most laptops.
Let’s take a look at two different scenarios.
Example 1. The laptop is absolutely dead.
When you plug in the power adapter and press on the power button, there is no signs of life at all. The laptop will not make usual noises, LEDs will not light up, the fan will not spin, the screen is blank and black, etc… In short, the laptop is dead.
What you can do in this case?
1. Make sure the wall outlet is working and the laptop DC adapter is getting power from the outlet. Try another wall outlet.
2. Test the laptop DC power adapter, make sure the voltage output is correct. You can test the DC power adapter with a voltmeter.
3. Let’s say the DC adapter is fine and the adapter outputs correct voltage. In this case unplug the power adapter from the laptop, remove the battery, wait for 1-2 minutes, plug in the adapter and try turning on the laptop again.
OK, you tested the adapter and it’s bad. If you decide to replace the original DC adapter with a generic one, you’ll have to follow this rule:
The voltage output on your new adapter has to be exactly the same as on the original adapter. The amperage on the new adapter could be the same or higher.
If nothing helps and the laptop is still dead, apparently the motherboard is fried or there is a problem with the DC power jack. It’s possible the DC power jack is broken and the motherboard is not getting any power from the adapter. In this case you’ll have to disassemble the laptop and replace the power jack. Check out this guide for fixing laptop power jack.
Example 2. When you plug the DC power adapter and press on the power button, the laptop starts making normal noises, the LEDs work properly but noting appears on the screen. The laptop will not start.
First of all, take a closer look at the LCD screen. Look at the screen under bright light. It’s possible that the image is still on the screen but it’s very faint. If that’s the case, check out these tips for troubleshooting laptop with backlight failure.
If there is no image on the laptop LCD screen, test the laptop with an external monitor. Connect an external monitor to the VGA port on your laptop and turn the laptop on. You can toggle video output between the internal LCD screen and external monitor by pressing Fn and F4 keys simultaneously on HP laptops, Fn and F5 keys on Toshiba laptops, Fn and F7 keys on IBM laptops. Other laptops may use different key combinations.
Let’s say the external monitor works fine but the internal LCD screen has no image at all. If that’s the case, your problem could be related to the LCD screen or the video cable. Also, make sure the video cable makes good connection with the motherboard and the LCD screen. Try reconnecting, reseating the cable.
In my case, both internal and external monitors were absolutely dead. Neither of them had image. That means the problem is not related to the LCD screen or the video cable. From my experience I know that this problem could be related to the laptop memory.
Try reseating the memory module, maybe it’s not making good connection with the memory slot. Try cleaning contacts on the memory module with pen eraser. Try moving the memory module into another slot. Try replacing the memory module with another known good module, it’s possible that your original module is dead.
If you have two memory modules installed you can try removing them one by one, it’s possible that one of the modules is bad. Try installing different memory modules into different memory slots.
In my case reseating, swapping the memory module didn’t help. I was pretty confident that my problem is not memory related and I moved on.
Try removing battery, hard drive and DVD drive and turning on the laptop without these components.
Also, try turning on the laptop with an external monitor when the video cable is unplugged from the motherboard. If the laptop start with video on the external monitor, apparently there is something wrong with the laptop display panel.
In my case removing the hard drive and DVD drive didn’t help. Unplugging the video cable didn’t help either.
I continued taking my laptop apart piece by piece and tested it after each step.
I removed wireless card, modem, disconnected the keyboard but it didn’t help.
I still wasn’t able to boot the laptop with video on the external monitor.
Finally, I disassembled the laptop and removed the motherboard.
On this picture you see my final test. The motherboard has been removed from the base and I assembled basic barebone system on my bench.
1. Motherboard. Like on most laptops, in my case the video card is integrated into the motherboard
2. CPU with heatsink and cooling fan.
3. Known good memory module.
4. The power button board witch I need to turn on the system.
5. Working DC power adapter.
Still cannot get any video on the external monitor. The system turns on, the cooling fan starts spinning but there is no video.
At this point I’m 95% sure that the motherboard is dead. CPU failures are not very common, so it must be bad motherboard.
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December 14th, 2008 at 7:17 am
Very helpful article and lots of good comments.
However I would like to ask and if possible get an answer.
HP dv 6000 series. Less than two years old. is Hardly moved and never bossed around.
A few months ago, when booting the LED button comes on and it starts making noises looking to start up but doesnt, When forced shut down (Pressing and holding Led button) and trying again it starts normally. Kept happening all the time.
Then all of a sudden stopped working. Now the Led light is on, power and battery checked all ok. the CPU fans spins onces then silence then “restarts” itself.
No beeping sound when RAM removed, done all the checks in the article, still nothing. So now i fear the motherboard is damaged.
My question. Am i missing something? What would damage the motherboard just like that on its own?!
December 7th, 2008 at 7:31 pm
Asif,
Could be memory related problem. It’s possible that one of the modules is bad.
Remove memory modules one by one, test the laptop with each memory module separately.
December 4th, 2008 at 4:32 pm
Had this problem….I know I sound like I know but really thing I got this one for you….O.K. first thing the story…..doing some paper work on the laptop (Gateway) went upstairs to retrive some papers …I come back and all I see is a black screen…I think its on standby but it never cuts on…..Restarted nothing…no bios no startup no wording no warning… so I thought it was the HD sent it for warrenty repair HD came back and its still doing the same thing….the only thing that work a little on both occasions were the indicator lights…and the fan..Power light on, battery light on…then the diskdrive light but thats it still black screen…..took the laptop components apart and tested…come to find out after testing it it was the RAM slot that was defective…only one of two worked and if you put the ram chip it to the non working slot “DEAD CITY MY MAN”….try
Skillz Unlimited MDA
December 4th, 2008 at 8:32 am
Sry for messaging again, but I gave you wrong information in my previous message. The fact is when I press the power switch, the laptop gets power as the lights are on. However I cant see anything on the screen and after a few seconds the laptop restarts and the same thing again happens. The situation is same for both internal and external monitor. However on some very random occasions the laptop starts working. My model is Acer Aspire 4530. Thanks.
December 2nd, 2008 at 3:35 pm
Mike,
I don’t think so. I believe this laptop should boot even if the cooling fan is unplugged from the motherboard.
Unplug HDD, DVD drive, keyboard. Unplug LCD screen cable from the motherboard. You need only motherboard, CPU (with heat sink and fan) and memory. Test system with an external monitor. If still nothing, most likely it’s bad memory or motherboard problem. CPU failures are not common.
If you installed new memory, apparently the problem is related to the motherboard.
December 2nd, 2008 at 3:31 pm
Asif,
Check the display properties. Make sure the laptop screen is set as a primary screen. Also, check the BIOS settings. Just in case restore BIOS to default settings.
I think it’s just wrong settings.
December 2nd, 2008 at 2:58 pm
I’ve got a toshiba M105-S3041 laptop.
I’ve disassembled down to board level and tried the bare bones test. I get the customary power led, the “ON” led and it appears to charge the battery. Turn on the laptop…it blinks the HDD light, but HDD never spins up (HDD is good). the CDROM will look for a CD, it will spin but won’t boot. Won’t pass POST. No beeps, no video, no HDD activity. I have re-seated everything. Again, bare bones is known good memory, mboard and power button board.
The CPU fan never turns on. I’ve not seen a bad CPU fan cause a PC not to POST but am I wrong?
Of course I’m looking at a mboard replacement. Just wanted to get some feedback.
Thanks
December 2nd, 2008 at 1:06 pm
HP Pavilion dv9535nr
Symptoms: no power. Light around the AC plug is lit. Pressing power button causes one flash of LED by power button and the power indicators at the bottom left of the case. Press it again and nothing happens. Unplug AC & discharge power, plug back in and I can get the LEDs to flash. No fan, no noise, nothing.
Steps already taken: Tested AC & Battery, not it. Reseated RAM & checked for failure, not it. Pulled out CMOS battery and reseated it, not it. Disconnected all HDs, NICs, etc.
Can’t see any cracks or discoloring. All connections seem secure. No water damage. Motherboard gone bad, power supply, or power button board? Any help is good help, I’m at my wits end.
November 28th, 2008 at 11:11 am
I have an ACER Aspire 4530. My laptop is working okay except that I cant see the boot sequence on my laptop monitor. It comes in an external monitor. However, in the laptop screen, once windows loads, everything becomes okay again. What can I do?
November 25th, 2008 at 10:49 am
Oscar,
I think it’s bad motherboard. The only test you can do at home is a visual inspection. If the laptop doesn’t start you cannot run any tests.
Here’s what you can try. Remove the keyboard bezel and take a look on the motherboard. Between the video cable connector and DC jack there is a small square chip with about 10-15 pins on each side.
Turn off the laptop, press firmly on the chip and try turning the laptop on while applying pressure on the chip. Will it start? In some cases M35X fails because of poor connection between this chip and motherboard.
Take a look at this post:
How to fix dead Toshiba Satellite M35X laptop