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AC Adapter issues Q & A.

Laptop switching to battery while connected to AC adapter

Q. While turned on, the laptop will switch to battery power even if connected with the AC adaptor (sometimes during boot-up, or after a while) until the battery drains out, he then goes to hibernation (the battery light is off). If no battery in the laptop, it will shut down, and the AC light will blink very fast. The battery (li-ion) will only charge up to 10%, where it then jumps right up to 100%, and will discharge from 100% to 90% then jump to 0%, go to hibernation, and fails to complete the process, shutting down. The adaptor makes a small "camera flash charging" sound, stabilizing at 19v. When charging, it repeatedly makes the "charging sound" Faulty AC adaptor? Or Faulty battery? Or Both?

A. First problem: The laptop switches to battery power even with connected AC adapter. Most likely you have a faulty power jack. It's either broken or loose. It's a known issue with laptops and you can fix it by replacing/resoldering the power jack or relocating it outside laptop case.

It also could be a problem with the power cord. Find a multimeter and check the AC adapter. See if the power cuts off when you jiggle the power cord. If it does, replace the adapter.

Second problem: The battery will discharge from 100% to 90% and then jump to 0%. It sounds like a bad battery.

Battery charging light is on even when power adapter is unplugged and laptop is stitched off

Q.The yellow light for battery charging does not go even after switching the laptop off and power jack is disconnected. Battery does not charge at all with power source connected.

A. First of all, try reconnection the battery if you haven't done it already.
The battery plugs directly into the connector attached to the motherboard. If the battery charging light stay on even when the power adapter is unplugged and the laptop is switched off, it's either bad battery or something is wrong with the motherboard. The only way to find the culprit is testing the laptop with another known good battery.

Also, you can try this. Remove the battery and plug in the power adapter. If the battery charging LED lights up even when the battery is removed, most likely you have a problem with the motherboard.

Battery charges only when the laptop is off

Q. Bought a Laptop without AC Adapter. I noticed it would charge the battery OK when the laptop was off but once in windows it would not charge the battery.

A. This is very important to choose the right AC adapter for your laptop. The output voltage MUST be exactly the same. If your laptop requires 18.5V you must use 18.5V adapter. The amperage should be the same or higher. If the laptop requires 4.74A adapter, you'll have to find an adapter which provides 4.74A or MORE.

While using AC adapter alone or battery alone, laptop works. While using them together, I am getting a problem.

Q. While using AC adapter alone or battery alone, laptop works. However while using them together, laptop LED lights blinks and the power meter for battery drops down immediately to 0% critical level, whereas the battery LED indicator says it's full. I tried to unplug the AC adaptor while it went down to 0%, then the power meter for the battery came back to normal 85%.

A. There could be a few different reasons why it happens:
1. It might be an issue with the BIOS. Make sure the laptop has the latest version of BIOS installed, update it if needed.
2. It might be a software related issue. If you have some kind of power management utility installed try uninstalling it and use Windows power management utility instead. Also I would try reinstalling the operating system if upgrading the BIOS or removing the power management utility does not help.
3. If you still experience the same problem even after upgrading the BIOS and reinstalling Windows, most likely you have a problem with the motherboard. Apparently the charging circuit is not working properly. I assume it's not a problem with the battery. You'll have to check the motherboard in this case.

Problem with my battery. 100% to about 40% the battery discharging normally then suddenly from 40% it drop directly to 2%.

Q. When I use only on battery, from 100% to about 40% the battery discharging normally (last about 1 hour) then suddenly from 40% it drop directly to 2%.
When I plug the AC cord, it won't directly charge (the charge LED is still not on). After 10 to 20 minutes it then starts to charge the battery (the indicator say that it can be charged to 100%).
If I turn-off the laptop and then charge the battery, it won't also directly charge but the delay is much shorter (maybe just about 1-2 minutes).
Is this the sign of a bad battery (when hot it can't be charged?) or maybe a bad AC adapter (not enough power to charge the battery when the laptop is turned on?)
Note that this symptom is always repeating when I use the laptop.

A. From the first part of your complaint description I can see that you have a bad battery. The percentage might vary, but the process of discharging is the same - the battery discharges fine until some point and then the remaining charge suddenly drops to the minimum. You'll have to replace the battery.
I'm not sure about the second part. Probably it's a battery related problem too. Just in case check if there is a newer version of BIOS available for your laptop. If you find one, upgrade the BIOS.

The battery is 100% charged but it will die within a few minutes as soon as the laptop is unplugged.

Q. When I unplug the power it will run off the battery, the battery icon says it is 100% charged and I have 2+ hrs remaining, but within a few minutes I get the "critical battery level" message and it will die. When I plug it back into AC power the battery charge light comes on (and will remain on for over a hour), but I will have the same problem with it dying as soon as it is unplugged. Do I need a new battery?

A. It looks like you have a bad battery. Here are some behaviors typical for a dying laptop battery:
1. The battery charges normally (according to the battery icon) but as soon as you unplug the laptop, it dies almost momentarily.
2. The battery charges normally. When you unplug the laptop, it discharges normally until some point and after that point starts discharging very fast. For example it might take 10-15 minutes to discharge from 100% to 80% and then it discharges from 80% to 0 for 2-3 minutes

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acer aspire notebook will not switch on after battery discharge even with mains adaptor plugged in. Help Noel


1. Remove the battery and the ac adapter from the laptop computer. Press the power button for about 10 seconds. This will discharge thee flea power from the laptop.
2. Connect the battery and the ac adapter. Charge the computer for about 30 mins then try to turn the computer on.
If this does not work, try to turn the computer on with only the AC adapter connected. If this works then it time to replace the battery.

Jun 26, 2011 | Acer Aspire One PC Notebook

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AC Adapter issues Q & A.


Well it can't !! Try as you might, jumping the battery contacts, leaving the Cmos battery out for a day, a week, a month, a YEAR will not Reset your Bios password! The same applies for the hard drive Hp dv1000 Battery Hp dv2000 Battery Hp dv6500 Battery

Jun 12, 2010 | Computers & Internet

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My laptop is not switching to AC mode even when plugged into Ac Power outlet. I work on battery mode and after full battery drain, the laptop goes into hybernation...once into hybernation it starts charging the battery. I bring up the laptop again it goes into battery mode only... never into AC mode even if the laptop is plugged into the AC supply.


1. You may possibly have a faulty power supply adapter. Contact the manufacturer and see if there are any call backs on the power adapter for you laptop unit
2. you may also have a damaged connector at the laptop connection. This will require repair by a technician.

Aug 03, 2010 | Computers & Internet

1 Answer

cannot get my computer to turn on


remove all external peripherals. remove laptop battery. remove ac adapter.
plug ac adapter to wall power socket without the laptop connected check if the ac adapter led will stays on. if yes then connect it to the laptop and check if the ac adapter led turns off. if yes motherboard laptop has problems and need to be replaced.
if ac adapter led stays off without connecting laptop, try different wall power socket, if still ac adapter led is off then replace the ac adapter.
if ac adapter has light stays on then connected to laptop but laptop cannot even power up even the ac adapter led is on then laptop motherboard needs to be replace.

Dec 09, 2009 | Dell Studio 15 Laptop

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