Why is my Samsung S3 not charging like it used to?

[NH1]

It started happening about a week ago, my phone has been disconnecting and connecting from the charger cable and not fully charging to 100% even if it was plugged in all day, more than 24 hours. I have been trying to figure out whether it is the charge port or the battery or the phone itself that is giving me trouble. It is definitely not the charger cable, as I have 3 different ones and they are all perfectly fine. I have removed the battery, re-inserted it and everything and restarted the phone several times. The phone itself runs very slow. The battery drains insanely quick even when I turn the phone off or shut down every application+data+wifi and everything in the background. I could not figure out whether my battery was water damaged either, the sticker on the bottom is bright red(no X's, just pure red), and yes I found a red leak once on the back of my phone, however I have never dropped it in water before(maybe snow?), but I always wipe it off real quick if I drop it. I have had this phone a little more than a year(bought it last July). If anyone has any ideas, or can verify whether it really is the battery or not, please let me know. Thanks!

 

[B. Diddy]

Welcome to Android Central! The behavior you describe sure sounds like a failing battery. The easiest test is to try a new or different battery. If you don't want to buy one, you could see if you can borrow a friend's--hopefully you know someone else with an S3.

A solid red sticker does mean water exposure.

 

[NH1]

Ooh okay thanks and thanks for verifying that! Do I also need to be worried about the port or the phone itself being water-damagedf? Everyone who Ive talked to who has an S3 has charging problems as well, I think its just a phone thing. But what if I buy the battery and it doesn't solve the problem... ??????

 

[B. Diddy]

It's hard to exclude a problem with the charging port, but that wouldn't explain the quick battery drain as well.