/diy/ - Do It Yourself

Anon, your computer is a sandwitch.

19V is the "ideal" voltage - actual voltage is going to be lower due to line impedance/resistance. The value you give is well within tolerance.

Are you sure your battery is fine?

>>478631
That kind of problem is mostly cause by either overheat or software error.

your laptop is overheating , keep it up and the gpu will be the first to go and your laptop will be a brick

>>478631

OP, how long does the laptop stay on before it shuts down?

>>478631
Are you using the charger than came with your laptop?

it turns on and dies within about five seconds, yeah?|

Fans dead or clogged.

Are you positive it's not the power jack on the laptop?
The jacks tend to become weakened over time with plugging/unplugging. It doesn't take much play for them to bust a connection.

>>478631
The adapter for laptops can be off my as much as + or - one volt. Your adapter is fine as far as voltage is concerned. I assume you measured the voltage under a load (measured while plugged in). Have you checked the laptop fans? If the fans aren't moving, either overheat or fan sensing circuits will shut down the machine to protect it. Have you tried powering it up on AC but with the battery removed? If it doesn't power up, you might have a bad DC jack on the laptop, or the regulator circuitry in the laptop have gone bad.

>>478645
It's not overheating, actually.
>>478647
It varies, when I used the battery by itself and the little bit of charge it had left, it never shut down, which is why I know the battery is fine. If I plug it in, it can shut down anywhere from the "Starting Windows" screen, to a few minutes past the log-in, but not long after.

>>478663
I mentioned this in a post after yours, I did the battery by itself, and proved that the battery is fine. I did the charger by itself, and it wouldn't even start. The power button would flash like it wanted to turn on, then nothing.

>>478655
I took the entire computer apart, and got to the motherboard, but the port looks fine externally. However, I don't know how to test for voltage once the motherboard is plugged in, as there are no wires going from the port. I'll post a picture in a minute

>>478666
I'm leaning heavily towards a bad DC jack in the laptop. A loose or intermittent connection could cause the laptop to do this.

>>478666
Sounds like the charger isn't supplying enough current.

>>478672
I thought so, too, but previous posters said the output I was getting was fine. It has to be the jack or something, but it looks fine, and I don't know how to test it atm.

>>478675
Even if the solder points are good, you can still have damage to the springy parts inside a jack. If you have another working power supply that you can cut the plug off of, you can temporarily solder it directly to the solder points of the DC jack. This will bypass any problems the DC jack may have. If it still doesn't like to stay on, you're looking at bad semiconductors on the laptop main board.

Update, I just tested the power jack itself, and it read 18.89v. It's worth mentioning that this was dropped, but it didn't seem relevant with the information I had. When I plugged in the motherboard, the jack was slightly wobbly, but I don't know if it would constitute reattachment.

>>478684
Was it dropped while plugged in?
Let me get this in here before I leave. It might be relevant for the future.
http://www.laptopjacks.com/

>>478689
No, but I tested the jack while it was plugged in, and it read 18.89v, is that too low?

>>478690
No. The voltage is fine. Most adapters for laptops can be off as much as + or - one volt. The voltage isn't a deal killer, although if it has bad caps in it, your voltmeter may not catch the excessive ripple. Normally the voltage drops a lot under load if the caps are bad.

>>478690
That voltage sounds fine to me, but you have no way of knowing how many amps are being made available. I'd suggest just replacing it.

>>478697
If the adapter can't supply the amps required, the voltage drops. Using voltage as a measurement is fine. I hope he's able to load the adapter properly with his tests.

>>478692
What are caps? I'm actually not fluent in computer language

>>478699
Sorry. Caps is slang for capacitor. They're used to filter pulsating DC that comes from a rectified AC source into a steady, un-pulsating DC source. In switching power supplies (like your adapter) they're under a lot of stress.

So, does anyone have a guess as to what the problem might be? I can take more pictures, if need be

>>478703
I'm leaning heavily on a bad DC jack in the laptop. If it doesn't hold the plug tight, a weak connection might read good voltage, but will have enough resistance to cause the voltage to drop under load. Can you measure the DC voltage at the laptop jack with the adapter plugged in and supply a resistive load at where it plugs into the laptop? The laptop doesn't need to be on for this. a 100 ohm, 4 watt resistor shouldn't drop the voltage that you initially measured.

>>478705
I don't really know how to do that, supply a resistive load

>>478710
Grab a resistor from you junk pile of spare resistors, and solder it to where the DC jack is soldered to the laptop board. I know you might not have a junkpile you can freely dig into, so you might have to order some resistors, or look around for some electronics your neighbors are throwing out to cannibalize some parts.

No one in this thread things this may be because the laptop was dropped?

One issue I ran into before was a power switch that broke/shorted. If the time that it takes for the computer to power off is exactly the same each and every time that could be a symptom of something that is not a power connection issue.

> I don't really know how to do that, supply a resistive load

well, one fairly common source of high-wattage loads are lamps, such as 12V car lamps, or 12V halogen house lamps. you'd need 2 in series to make sure they dont burn out. other suitable loads are toasters, heaters and hair-dryers, which will all draw about 1.5A from 19V.

18.92v is fine as long as its not dropping too much under load.

Check your cable for any kinks or areas where it would have been smashed in a drawer or something. I have had power supplies with damaged cables only kind of function due to a partial short.

If you can check the voltage while the laptop is on and plugged in it would be good.