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.
May 14th, 2009 at 6:28 am
Hi,on my laptop hp dv9005us, i have a light in power jack but don`t have any light on front panel,no light like charging, when i try to turn it on i have no response.
i teste the power jack and got 19.2V but i could`nt find with fuse is…… or if have one.
May 13th, 2009 at 1:27 pm
Hi.
My computer does not turn on as well.
I tested the jack and got 19V.
I tested the fuse, but 0V.
The Power LED of the laptop is ON.
Is the problem with the fuse, even the power LED is on?
I appreciate any help.
Thanks so much.
May 13th, 2009 at 1:22 pm
Hi. You said that the problem can be in the jack or the fuse. In either these cases, does the Power LED is ON? Thanks.
May 12th, 2009 at 4:18 pm
I have a Hp Laptop that will not turn on. I got it brand new and after a year it just went dead on me one night after leaving it on the bed running,. Im thinking that maybe it overheated and turned off because it did that before but this time its not turning back on. When i press the power button the led’s will turn on and the fan would spin but then it goes right back off. What could be the problem and how can i fix this ?
May 5th, 2009 at 9:59 pm
Amber,
It’s hard to tell if your jack is broken without looking at it.
1. This problem could be related to the power cable connected to the adapter plug. Maybe there is a short inside the cable and when you move the plug, you actually shorting wires inside the cable. Before you take apart the laptop, test the power adapter with a multimeter. Make sure the adapter outputs correct voltage even when you move the cable.
2. Is your jack soldered to the motherboard? In most cases you don’t have to replace the jack. You can fix the problem by resoldering the jack back to the motherboard.
May 3rd, 2009 at 8:38 pm
So, I happen to know the problem with my laptop. Somehow, the DC-in jack is loose and will only register the adapter if it’s pushed in a certain way. Does this mean the jack is completely broken, or can I fix this myself somehow? I don’t want to fool around with it unless I know I can fix it.
Thanks!
April 22nd, 2009 at 12:23 pm
Louise,
1. Turn off the laptop, unplug the adapter, remove the battery. Wait for a few minutes. Plug in the AC adapter and try turning it on.
2. I assume you tried replacing RAM with a known good module, so it’s not the RAM problem. Try removing DVD drive, hard drive, other devices you can access and start the laptop without them. If you still experience the same problem, apparently you have a bad motherboard or video card. I don’t know if in your laptop the video card is a discrete module or it’s integrated into the motherboard.
April 21st, 2009 at 10:28 pm
Hi, i have a Hi-Grade laptop with 2GB RAM. Recently it has been freezing completly and ctrl+alt+del wont work. So I’ve turned it off via the power button. But now it wont tun on at all. The power light and the wireless light stay on when the power button is pushed and the fan comes on. I have tried replacing the memory modules and stil the same problem. What else can i do? Also my data is not backed up because I was in the process of doing so.
April 21st, 2009 at 12:49 pm
Kaliy Tech,
Unfortunately I don’t have any tutorial on this topic (yet). First of all, you’ll have to find the fuse. It’s usually located close to the power jack. After that you test the fuse with a multimeter and if it’s open, replacing the fuse might help.
April 20th, 2009 at 10:03 pm
Hi.. do you have more information on how to replace the fuse on a motherboard ? I wasn’t even aware there was such a thing
Have a laptop in with no power whatsoever.. no lights.. no sounds..nothing. battery tests at 100% when pushed.. but doesn’t power at all. Thank you.