HomeLet’s say your laptop does not start at all. You plug in the power adapter and press on the power button, but the laptop will not react. It’s dead and the power or battery charge LED will not light up.
What could be wrong? Is it bad power jack or the motherboard is dead?
By the way, the power jack aka DC-IN jack is the power socket on the side or back of your laptop where you plug the AC/DC power adapter.
I’ll explain how to perform basic troubleshooting and find out what is wrong. This is only for experienced people, who know how to disassemble laptops.
First of all, test the AC/DC power adapter with a multimeter. It’s very likely that there is noting wrong with the laptop and your problem is related to the power adapter.
If the adapter tests fine and output correct voltage, disassemble the laptop and remove the top cover.
As you see on the first picture, in my laptop the power adapter plugs into the DC-IN power jack which is connected to the motherboard via a harness.
In some models the DC-IN power jack is soldered directly to the motherboard.
Plug in the power adapter and measure voltage at the point where the DC-IN jack or DC harness (like in my case) connected to the motherboard.
If you are reading the same voltage as on the AC adapter, it means the power jack or harness works properly and the problem is related to the motherboard.
If there is no voltage, most likely there is a problem with the jack or hardness and it has to be replaced.
By the way, in some case the problem could be related to the fuse which is usually located somewhere very close to the power jack/harness connector. You can test the fuse with a multimeter.
If the fuse is bad, the motherboard will appear to be dead even if there is nothing wrong with the power jack and AC/DC adapter. If that’s the case, replacing the bad fuse should fix the problem.
January 3rd, 2011 at 5:54 pm
Hi , i have a gateway nv52 with power adapter plugged in only a blue light will come on no power gateway tech support does not have a clue however this a know issue you see all over the internet brought from vendor there tech does not have a clue was wondering if this is a bad dc jack or muti function power button board or power cable any advice will be helpful
December 29th, 2010 at 8:48 pm
Hi! I have a Dell Inspiron B130 that crapped out on me mysteriously. It is completely dead. No LEDs light up no matter what i press. When plugged into the computer, the AC adapter blinks. When not plugged in, it is a solid green light. I tested it with a multimeter and found it was fine at 19 volts. I also bought an extra battery, but the laptop did not power on so I don’t think that was the problem (although I wasn’t able to confirm this since I couldn’t measure their voltage).
As for the power jack, the voltage drop from the positive pin (the one perpendicular to all the others, i am thinking) and all of the negative ones was only between 3 and 4 volts, significantly below 19 of the adapter.
My questions:
Does this confirm the diagnosis of the power jack? Would 4 volts be insufficient to give me any response from my computer whatsoever? I couldn’t tell if the soldering on the jack was damaged or not, or what else could be wrong with it. Or perhaps I didn’t put the negative test lead of the multimeter in the right spot while measuring? I put it on all the pins except the positive one, and they all measured the same. If it is a motherboard problem, shall I begin salvaging the parts or is it repairable?
btw, I have also read your tutorial on the B130 DC power jack repair.
Please let me know what you think.
December 8th, 2010 at 11:48 pm
viraji,
Does the battery charging LED have to blink when laptop connected to AC and battery installed? I believe it should light solid.
If the laptop doesn’t turn on at all and all you get is battery charging LED, this could be bad power switch board or failed motherboard.
It’s really hard to troubleshoot a problem like that without seeing the laptop.
December 2nd, 2010 at 2:22 pm
Hi ,
Im using a HP dv2500 laptop. its not switching ON at all. but when i connect the power cable (without the battery) it shows the battery charging LED. when i connect the power cable with the battery connected the LED not blinking.
What you reckon the prb could be? Motherboard or fuse?
November 29th, 2010 at 2:06 pm
My daughter has an acer to the she uses everyday and it wont work without battery . I did notice that when i first plug it in the battery light will be green for a minute then goes to solid orange
November 28th, 2010 at 11:21 am
Beth,
you said:
1. I have done the rundown with the power cord and the jack its all good.
2. No it will not turn on with power supply alone.
So, the AC adapter is good, power jack is good but the laptop with not turn on when battery removed.
This sounds like motherboard failure to me.
November 28th, 2010 at 6:53 am
No it will not turn on with power supply alone.
November 25th, 2010 at 9:54 am
Beth,
Remove the battery and try turning it on just with AC adapter. Can you start the laptop when the battery removed?
November 25th, 2010 at 9:35 am
I have an acer about 2yrs old when I plug the charger in the battery light will turn green for a second then it goes to yellow and it will not charge or power up. I have done the rundown with the power cord and the jack its all good. Got any suggestion?
November 21st, 2010 at 1:02 am
Mido,
It’s hard to tell what is wrong with the laptop.
You can try taking it apart to barebone system and see if it works.
Disassemble it as much as you can at test with an external monitor.
Basically, all you need is motherboard, processor and memory to start your laptop with video.
Take a look at this guide:
http://www.laptoprepair101.com/laptop/2008/06/14/laptop-dead-troubleshoot-the-problem/