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.
If you find this article useful, please consider making a donation to the author. Thank you!
September 9th, 2008 at 8:44 pm
Jose,
Take a closer look at the power jack. If you have a voltmeter, you can test if the power gets to the motherboard when the power adapter is plugged in.
If the motherboard gets power from the adapter but has no signs of life, it’s possible that you have a blown fuse witch can be replaced by a technician with some soldering experience. If the fuse is OK, most likely there is a problem with the motherboard.
September 7th, 2008 at 7:14 pm
i have a dead dell inspiron model PP10L.
my dell was working fine then all of a sudden it will not turn on. no lights no noise no sign of any life in it. i tested to see if we had power to the power cord/adapter and i get the 20 volts. we now that is ok i have removed hdd, battery, and still no sign of life. i was thinking the maybe it is my dc jack. when i plug the cord to the laptop there is a little play but it does not matter if i wiggle the cord in any direction and attempting to power up its still a no go. i guess i need to take the laptop apart and see if the jack is broken or loose. has anyone had any problems of this kind with there dell. thanks
August 27th, 2008 at 1:06 pm
Kris,
Sure. Check out this post: Accessing notebook hard drive using USB enclosure.
August 27th, 2008 at 12:43 pm
yeah.. its dead. lol
now im gonna have to decide between replacing motherboard or buying new laptop.
is there anyway to get my data from the harddrive using my desktop?
August 26th, 2008 at 10:02 pm
Kris,
1. Make sure the power adapter is working properly.
2. Minimize the laptop as much as you can as I suggested in the post. Test the laptop again. If the laptop still turns on for 2-3 seconds (without video) and then turns off by itself, probably it’s related to the motherboard.
August 26th, 2008 at 7:04 pm
Can anyone help me troubleshoot whether my motherboard is dead?
Giving you only information that when I press the on button on my Inspiron E1405, which is attached to the wall even or running on battery, the LED lights go on (screen is black). After ..mm.. about 2-3 seconds of the LED being on (while still with black screen) the laptop powers off.
Dead?
August 19th, 2008 at 5:48 pm
Sam Modonpour,
Thank you very much for your really valuable comment.
August 19th, 2008 at 3:36 pm
There are few more steps you can take to fix the motherboard, rather than just saying its dead.
For example if you follow the editors steps and the laptop turns on and no video on the LCD, its apparently the video chip on the motherboard. This problem usually happens to P4/PM/Centrino Boards. The only thing you should do is to reflow the chip, which you can either do it with a expensive oven, or a good heat gun, the one I use is “Milwaukee 8978-20″ since it does not have L shape handel its easier to hold while sitting at the table and cost only $99 in Amazon. The other thing you need is a Infrared Thermometer like Fluke 63 which is what I use and you can get it on Amazon for $130, to measure heat of the core while reflowing it. To know more about the reflow cycle watch the video “Re-flow Video Card IBM T41p Latop motherboard.” Thats how you fixed the video problem.
Lets get back to the main problem, if your laptop does not turn at all, and you have cheked the power jack allready, check the fuses on the board beside the powerjack, always check those with the buzzer on the multimeter, If the buzzer does not beep across the fuze that means…. Another thing to remeber is watch the board closely, and try to find any visual defects, usually if the SMD components burn their color changes and they sometimes crack too so if you look carefully you might be able to point it visually. Wherever you see there is food crumps or dirt or you might suspect there is a short in the circuit clean it with Isopropyl alcohol and a tooth brush. You can also test the SMD component of the power circuit with the buzzer mode on the multimeter. The buzzer on Good “C” Capacitor should not beep, On the Good “L” Inductor should beep, On the resistor depends on the Resistance so if small R beeps if not test it with the resistance measurement on the multimeter if it is Zero or Open the resistor is bad. Check the on board SMD power button test it with multimeter too I have exprienced after testing the whole board the power button is bad. I will add on stuff later. Cheers
August 13th, 2008 at 7:52 am
mel,
Please let me know if you find any source on the web.
August 13th, 2008 at 5:40 am
cj2600,
I will keep researching to find someone out there willing teach more advance stuff repairing laptop motherboard. I don’t give easy.