Car battery rating on 2.0 TDI KL

[LeoSlo]

Bought my KL ST 2021 2.0 TDI two days ago. Yesterday while driving it's starts to go off with all kinds of system failures (Drive system, Travel assist, Side assist), and on top of that, the oil temp. meter is going nuts, starts fluctuating and rising violently between 70 C and 130 C.
Talked to a few mechanics and my dealer (official VAG representative in my country) today, and one of them says it might be a battery problem.
I decided to chase that idea and go to a shop nearby where they have a more proper battery diagnostic tool and it spits out this:

He said the battery is shot, probably the reason for all the failures.
Anyone have experience with this?

I'm calling my dealer tomorrow to get it replaced. It's covered by our consumer protective law which ensures me from things like this.
But still, I'm not 100% sure, if this is the root cause.. I might be a bit anxious when it comes to expensive things breaking down Then again, who isn't..

 

[LeoSlo]

Btw this is the oil temp. going nuts I was mentioning. Car behaves and sounds normal though

http://imgur.com/a/vJcSaSZ

 

[Seriously?]

Battery "resting" voltage should be around 12.6V
Getting close to the 12V mark suggests it's almost fully discharged.
Modern car electronics hate under-volts and can display the symptoms your car is showing.

 

[LeoSlo]

Yeap, I thought so also. I just sat in right now for a few minutes trying to set a few things up and the 12V battery warning showed up.
I'll get it replaced asap and post here after, to confirm if this resolved all my issues

 

[Yern]

I had none of the other issues 12 months ago on my previous 22 plate MK4 except for the fluctuating oil temp, exactly the same behaviour. The dealer replaced the oil temp sensor and this cured the problem. Perfect since until I just changed the car.

 

[LeoSlo]

Yesterday, I was at the SEAT dealer so that they could replace the battery. They changed it, and we went on a test drive. The errors were still there, and the oil was still swinging. All in all, the mission failed successfully. My head was spinning on the way home, not a really good experience with a car I was anticipating the most out of all I had.
This morning I took it to the washing station and then took it for a short drive ca. 30min. No errors, no failures and most of all, the oil temp. wasn't swinging...
It was rising slowly as it normally should, and stayed stable.
I'm dumbfounded, no idea what is happening.
I'm thinking software issues, since from what I've read I seem to have an old version (1804) and I've tracked much more current versions for it. Just don't know how to update. I'll have to search for this.

 

[cairus]

I know that the combined oil sensor is prone to failure. It was replaced and everything was fine again.