Dell Inspiron 15 3521 Charging problem.

[swarup287035]

My laptop was working fine but one day all of a sudden while the adapter was connected it went into the battery only mode (such as, the adapter is not connected) then I plugged out the adapter and then plugged in again and it went into the adapter mode but then after a few seconds the LED charging indicator on the laptop turned off and I started getting the message, "plugged in, not charging".
These problems keep on alternating. Either my laptop behaves as if the adapter is not connceted or it says "plugged in, not charging".
My laptop boots fine with only the adapter (no battery), so clearly the adapter is functioning properly.
So is it a mainboard issue or a battery issue?
Is there any way to confirm? Because if I buy a battery and the problem doesn't solve then my money will be wasted for nothing.

 

[webworkings]

It could be the charger. Try charging it when the laptop is turned off and see if it charges without issue. If it does, then I would replace the charger.

If it still has issues, then I would start looking at the motherboard. I say that before the battery due to the fact that you said it acting like it is not connected sometimes.