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.
February 1st, 2011 at 8:42 am
Nocturnal Lunacy,
It sounds like motherboard failure. I think when you apply pressure on the palmrest, you actually applying pressure on the motherboard.
It’s possible the motherboard has a crack somewhere and flexing it (applying pressure on the palmrest) fixes it temporarily.
Here’s how to narrow down the problem:
You can disassemble the laptop and test motherboard outside the laptop base. All you need is the motherboard, CPU, memory and external monitor.
If it still fails when you apply some pressure directly to the motherboard, most likely you have a bad board.
Check out this post: http://www.laptoprepair101.com/laptop/2008/06/14/laptop-dead-troubleshoot-the-problem/
January 31st, 2011 at 1:07 pm
I have an Acer Aspire 5100 that has some major issues. When I turn it on it gets almost past the boot screen and I get two beeps and then the laptop goes to the error screen saying that it can’t find the hdd, but yet lists the hdd number and all and asks me to continue or cancel which powers off. There are times when I will get a boot message saying that PCI 4 is trying to use the wrong power or whatever. I can’t remember. But if I press on the laptop next to the touch pad directly under the sticker that says AMD, it will boot fine. I have to press hard, but sometimes it won’t. Sometimes I don’t have to press on it at all and it’ll boot fine. I have taken the laptop apart and found that where I was pressing is the CMOS which is attached directly to the MOBO and found that it was slightly loose, not disconnected, but loose so I re-soldered the battery back to the MOBO and then the laptop booted fine for a while and then it started doing the same thing. I noticed that the ground of the battery was facing the underside of the PCI slot and when it gets pressed down, it makes contact with the CMOS battery. Could it be that when I press down on the PCI slot housing and ground the CMOS battery, that that is the reason for the boot problems, cuz the CMOS battery has a bad ground on the MOBO. What do you think?
January 29th, 2011 at 8:07 am
i have compaq nc6230 its on by bettry but not on via dc power i was very confuse after that i resold isl power ic but i could not get more help after i procced just now ….
January 27th, 2011 at 6:39 pm
Hello,
I have an Acer aspire 5741. Just got it back from Acer as I claimed the warranty on it. The original problem that it wasnt charging and the power led and charging led were blinking. First Acer refused to repair it and asked cash for a replacement of motherboard, though writing letters to their CEO, country manager did the trick and they sent it back to me after repair.
Now the problem is, as soon as it came back, I plugged it in so it could charge. But after 5 to 10 minutes the charging led on laptop started blinking. The laptop also didnot boot up. the power led would come on for a second and woud not turn on. Moreover, there was some strange sound coming from the laptop and the charging led on laptop started blinking again. I turned off the charger, but the power light kept on blinking. Then I took out the battery and placed it back. It seemed to charge like normal for 10 minutes then the charging led started to blink. Then after 10 mins it started to charge normally but again after 10 mins or so the charging led started to blink.
Another funny thing is when I turn off the charger and reomve the cord from the d/c jack, the charging light keeps on blinking.
I tried another charger but same result. Another funny thing is when I turn off the charger and reomve the cord from the d/c jack, the charging light keeps on blinking
January 24th, 2011 at 9:03 pm
marsha,
Possible memory (RAM) failure. Do you know if your laptop has two memory modules installed? Try removing them one by one. If one of the modules is bad, the laptop should start properly with the second module.
January 24th, 2011 at 8:48 pm
Heather,
First of all, I would test the AC adapter. It’s possible the AC adapter is bad and the battery has no charge to start the laptop.
Make sure the AC adapter outputs correct voltage.
Also, I would test the laptop with another known good adapter. Why? It’s possible that your original adapter outputs correct voltage BUT doesn’t work properly when loaded (plugged into the laptop). It’s not a common adapter failure, but I’ve seen it happening before.
What happens if you remove the battery and try turning it on just from AC adapter? Same brief light flash and then dead?
For proper diagnostic, it’s necessary to disassemble the laptop and check voltage on terminals where jack connected to the motherboard. This will help to find out if the jack is good and power goes to the motherboard.
If the motherboard gets power but the laptop will not start, probably it’s bad board.
January 24th, 2011 at 8:04 am
Hi,
Thanks for all the great information here! My Presario C700 laptop won’t start and has a symptom that I haven’t seen described anywhere:
With the battery installed and AC adapter plugged in, the LED light on the power jack and some indicator lights on the keyboard are on. When I press the power button, the power button also lights up briefly, and then all lights go dark and stay off. If I press the power button again, nothing happens, and the lights don’t come back on. The lights only come back on if I unplug the adapter from the laptop and plug it back in. I tried the reset procedures recommended by HP, and there are no blinking lights or other diagnostic clues.
The laptop died suddenly while I was using it, with no weird noises or indications of overheating. The battery was fine at the time and the adapter was plugged in.
I can borrow a multimeter but haven’t yet. Does this sound like a replaceable component, like a bad power button board, power jack, or fuse? Or does it sound more like a dead motherboard? Thanks!
January 22nd, 2011 at 9:09 pm
I’m in need of some advice. I have a Dell XPS 1530, that when plugged in and powered up, the only lights that come on are the battery charging light and the wifi light. The fan also comes on, but no lights on the power button and the screen is blank. Any suggestions of what it might be?
January 21st, 2011 at 3:43 am
I have HP DV 6000 series Laptop, everything was working fine till last month while playing game screen suddenly filled with color stripes, I turned it off and restarted again, everything went fine for sometime and later same thing happened. Now when I try to turn it on led and fan runs for a second and goes off and again after some second led and fan runs and again goes off. Nothing shows in the screen.
Here are no HP care centre, local maintenance shop says it’s motherboards fault and needs to change whole board.
Is this really a problem of motherboard?
Do I have to change whole board?
How do I solve this problem, sir?
January 7th, 2011 at 9:00 am
sean,
I think most likely this is motherboard related failure. With a bad DC jack, the laptop should still start normally from the new battery (I assume it was charged).
No, 4 volts is not sufficient to start the laptop.
There is a chance that your laptop doesn’t start because the AC adapter is failing. Maybe it’s not working properly when loaded (connected to the laptop). I’ve seen failures like that before.
Let’s say both batteries has no charge and the AC adapter fails when connected to the laptop. In this case the laptop will not start because it just not getting any power. Replacing the AC adapter might fix the problem.
In short, test your laptop with another known good AC adapter. If it doesn’t help, most likely this is motherboard failure.