Battery change - is coding required?

[djohnson]

Hi, apologies if this is a basic question, I’ve tried Google with mixed answers. My son has a 2013 1.2 Polo, we’re experiencing issues with it which I’m fairly sure are caused by a failing battery. Given it’s not a big cost I’m wanting to try putting a new battery on it to see if that cures it. I’m fine to bolt a new battery in place and connect it up, however I’m unclear on whether modern cars need some sort of coding so the car is aware it has a new battery and hence adjusts the alternator output accordingly? Thanks for any replies.

[tapkaJohnD]

You could try connecting the new battery in parallel to the old before you swap them.
Then there is no failure of battery supply while you make the change, nothing to trigger 'new battery alarm' in the ECU.

John

[craig1912]

My sons 2015 Polo did need coding when the battery was changed.

[CorradoTDI]

It should only be required if the car is Start-Stop so will have either an AGM or EFB type battery.

Even if it does, you'll still be able to start the car without coding initially - you may have to calibrate the steering by moving lock to lock to clear the warning light.

[djohnson]

Thanks all.

[Peanut Gallery]

Ford owner here, if you replace the battery with a like for like (AGM with AGM, EBC with EBC) then all you do is a quick reset of the battery monitoring system, this tells the computer it has a new battery and just to charge it accordingly.

If you swop from AGM to EBC, then more coding is required.

[ro250]

Peanut Gallery said:

Ford owner here, if you replace the battery with a like for like (AGM with AGM, EBC with EBC) then all you do is a quick reset of the battery monitoring system, this tells the computer it has a new battery and just to charge it accordingly.

If you swop from AGM to EBC, then more coding is required.

I went through similar research when changing my BMW battery. The internet is awash with rubbish!

As described here, there are 2 things which are interchangeably referred to but are different:

Coding - When the vehicle needs to be told of the new battery in order to operate (e.g. as above when changing type)

Registering - Telling the car it's had a new battery as apparently modern cars adjust their charge patterns based on the age of the battery. Halfords did mine with an OBD tool (but only because I asked them to!).