I m have a laptop without the ac adapter and its an older modle serial no. is 82143976p and i want to know is which one to get for it.

Without knowing the specific model laptop...you may be able to try the ac charger of a friends dell laptop and see if that will charge. Your issue may be finding the right size connector. Easiest..go to dell.support and enter your model serial # found on the bottom of you laptop or on some models pop out the battery, sticker in there.

If the laptop is still working when it is plugged in , then the ac adapter is good and the battery is just bad. If the laptop will not work when it is plugged in then more than likely the ac adapter is bad.

Turn the on/off switch to off.
Hold down the "speed increase" and "speed decrease" buttons while turning on the switch at the same time. You will be in the "diagnostics" menu. Scroll to the "elevation calibration" option.

I know, it is an older post.

if the pc is not getting power without the ac adapter then most likely the battery is dead if it does not take a charge via the ac adapter then then the battery is no good or the ac adapter is busted

1. remove battery and ac adapter 2. connect the ac adapter to a different power socket without connecting to laptop. just check if the power led on the ac adapter will lit on. 3. if ac adapter led is on, connect ac adapter alone without the battery then try to power on the laptop. check if the power button or the media controls lit on if not then replace motherboard.

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.

try connecting ac adapter alone without the laptop, check if ac adapter light will stay green or blue.
try another power outlet using the ac adapter alone without the laptop check if the ac adapter light will stay as green or blue. if all fails replace ac adapter.

if ac adapter stays green or blue try connecting to the laptop without the batt, check if the ac adapter light will stay on, if yes then try connecting ac adapter to laptop with the batt plugin check if the light stays green. if not update the BIOS. if fails replace motherboard.

The problem you described here shows that, the case is not likely to be a battery problem, but the laptop AC-Adapter (Charger) problem, because, the red light you are seeing shows that your battery has rundown, and even when you plug-in the adapter to AC, it still blinks red, showing that the AC-Power is not charging it. I would suggest that you get another Laptop AC-Adapter (The Charger), or try it with a friend's own first, then you'll see that the problem might not be with your battery but your AC-Adapter

you can use any laptop AC adapter DC output-16V and 4A (current). if its jack size natch your laptop DC jack.
if the adapter DC current less than 4A (over 2.5A at least) you should only make the battery charging without laptop turn on!!!
please take a rating let me know how much helped you thanks!

Verna,

This site has the adapter you need for you laptop.

http://www.shoplaptop.net/reacpoadforw36.html

Hope this helps,

Eric