12v Battery Replacement

[spembo]

I suspect I may need to replace my 12v battery. I have had 12v warnings in the past, usually when camping and doors have been opened lots, although it’s always just said something about driving carefully and goes away after a short drive (although never did this in the early years)

I’ve recently been getting parking sensor issues, usually at low speed or braking, but usually disappear. Possibly more relevant on sunny days. I don’t believe a damaged sensor, as been through that scenario in the past, so suspect maybe linked to battery. The battery read 12.4V on the multimeter tonight, which I know is on the edge.

I’ve no problem fitting the battery, but have been reading about potentially needing to update the serial with OBDeleven (which I don’t have), I’m not sure if this is valid for mk4, but also read if close enough match to just drive around and it will eventually adjust its charging profile.

Does anyone have advice?

Car is a few months over 3 yrs old.

 

[KoNG]

I replaced my battery about 3 months ago (First Edition 2020). The car still worked fine, as it's a 1.5 Etsi, but when I measured the battery with a device from Amazon, it showed 56% battery life. I had already had a problem when the car died completely; therefore, I bought a battery jump-start. As the car is now parked outside over the winter (it was in the garage before), I didn't want to be in a situation where it wouldn't start because the battery would just die on its own due to its age. I coded the new battery, and as I did my research, it's important to do so, as battery charging is affected by its age, and the unit adjusts its charging curve to adapt to its life. I would recommend coding it.