Power Problem of my Laptop?

i have a lenovo laptop which worked fine. but suddenly it stopped charging. the battery indicator shows “77% remaining (charging)” but does not increase anymore. the laptop starts on a/c power but does not start on battery. as soon as i remove tha charger the laptop suddenly powers off.. what seems to be the problem and how do i resolve it???
plz help…

Since the A/C is still working, it shows the current is still there. The problem lies inside the connection between the battery pack and the charger. Yes, your laptop does work normal; follow these DIY steps.
Leave power plugged in

Make sure the computer has been charging from the power plug for at least a few hours before attempting to unplug it.

Remove and reconnect battery

In some situations the battery can become loose. Removing it and then put it back into the laptop. If you need assistance removing the main computer battery see document CH001128.

Refresh battery

Some laptop manufacturers allow for batteries to be refreshed through the CMOS. Refreshing a battery can help restore older batteries and give them more life and in some cases can report if the battery is bad.

Replace battery and/or AC adapter

If the above steps have been completed we suggest the next step be to replace the battery in the computer and/or AC adapter. In some situations it can simply be a bad battery preventing it from being charged.

If your computer is still in warranty we suggest skipping to the next step.

Service laptop

If after following the above steps the computer is still unable to charge the battery it’s likely that a component within the laptop has failed and will need to be replaced before it will be capable of charging the battery again.

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