Samsung S9 overheating and draining battery

[Ezechiel20]

My Samsung S9 is overheating and draining the battery fastly. Even when I am not using the phone and all connexion disconnected. 

[RedDogRabbit]

It's certainly possible that an app is contributing to the issue, but if it's the original battery, and it's 6 years old, there's no way that the battery is "good", regardless of what the Diagnostics say. 

[JSL12]

I guess the battery is hit or miss because my girlfriend's phone is about a year older than mine and hers is fine.  Maybe it is because I got rid of the protection plan from Verizon on the phone I've been paying for all this time then this happens 2 days later.  A little coincidental :)

[JSL12]

And as quickly as it started the problem went away.  As of Friday evening 3/8 around 6PM EST the issue stopped and the phone has been fine ever since.  No idea what changed.  Of course I ordered a new S23 FE so that's probably why LOL.

[bednarcm]

I have the same problem, it started yesterday. S9+, battery was changed about 2 years ago. It's not battery problem. Phone is warm, even if screen and all applications are off. After 4 hours with about 30 minutes SoT battery is empty.

I know, this phone is old, I consider change to s23u, but... what if this unknown problem will happen also on new phone?

[RedDogRabbit]

Unless you restore an app or Settings issue from a previous phone, to your new phone, I don't see any way for the issue from an old phone, occur on a new one.

About 2 years for a battery, is not unheard of to see it's performance diminish. 

Maybe it IS something else, but still sounds like a battery issue to me. 

[DDQC]

Except there are reports from people who just bought a new phone less than a month ago having the same issue. Any explanation for that?

[RedDogRabbit]

First thing that comes to mind, if they restored a backup from their old device to the new device, they could have easily restored the problem to the new device. 

[DDQC]

Same issue as of couple of days ago.

Just changed the battery and the issue persists.

I wonder if they had some sort of a breach and there is malware on the phone. 

[DDQC]

So yeah, probably not malware either, run a reputable antivirus on the phone and nothing came up. 

[DDQC]

So, same as someone else reported - out of the blue the issue stopped. Clearly something has been happening in the background that caused this. I am guessing a third party app...