u/Hot-Tiger-3139

I have a Mercedes C300 s206. The car is 2.5 years old with 20.000km. A while ago I started getting notifications on my phone that the 12V reached a critically low. The car itself also showed it once I got in.

I went to the garage to measure the battery and it appeared to have only 58% of its capacity left, so it got replaced. This was about 3 weeks ago.

Now this evening I got that same message again on my phone. Which I would not have expected since the battery is only 3 weeks old.

When driving, the car seems to charge the battery normally and after the drive the app shows that the battery is charged again. But these messages pop up after the car has been parked for a while.

Anyone has any ideas what the issue might be?

Thanks!