Hi all, the battery on 2015 S3 is feeling a bit weak at start up and thibk it needs a new one. Do I have to have it coded after and if so can it be done by Carista or does it need to be VCDS?
cheers
cheers
Battery change / coding
- Thread starter Russsimps79
- Start date
Carista claims to be able to code a new battery in your version of S3.
What type of battery is currently fitted, an EFB or AGM?
I've had a bit of success by running a "reconditioning" profile on a 2015 EFB - but don't try that on an AGM version, also you could try changing the serial number, or just changing a single digit of the serial number as that might prompt the battery management system to charge that battery a bit better.
If replacing an EFB with an AGM, remember to change the battery type using Carista from EFB to Fleece if that option is available, if not change it to AGM.
What type of battery is currently fitted, an EFB or AGM?
I've had a bit of success by running a "reconditioning" profile on a 2015 EFB - but don't try that on an AGM version, also you could try changing the serial number, or just changing a single digit of the serial number as that might prompt the battery management system to charge that battery a bit better.
If replacing an EFB with an AGM, remember to change the battery type using Carista from EFB to Fleece if that option is available, if not change it to AGM.
Just for clarity……
Coding a battery is not a necessity when you replace your battery, it’s a recommendation.
Battery charging systems have become more intelligent in recent year, and they alter the profile of the charge to maximise the life of the battery.
Battery charge and discharge characteristics change as the battery ages, and “coding” (you can just change one digit of the battery code) simply tells the onboard electronics that a new battery has been fitted, and resets the charging profile to “new battery”.
You won’t damage the battery if you don’t code it to the car, but it may have a slightly shorter lifespan.
Coding becomes a bit more important if you replace your battery with a bigger, higher capacity battery, because a larger battery needs a higher charge profile to maintain at full 100% charge. Also some MMI systems can display battery info (state of charge etc) and may not display correctly if the battery is not correctly coded to the car.
iI you’re changing to a larger battery, or different battery type, you need to change more than the battery code, you also have to select the battery type and capacity. It’s easy to do with the likes of VCDS (other tools are available…) and all the info you need is usually on a label attached to the new battery, or you can just scan the QR code found on most new batteries these days
Coding a battery is not a necessity when you replace your battery, it’s a recommendation.
Battery charging systems have become more intelligent in recent year, and they alter the profile of the charge to maximise the life of the battery.
Battery charge and discharge characteristics change as the battery ages, and “coding” (you can just change one digit of the battery code) simply tells the onboard electronics that a new battery has been fitted, and resets the charging profile to “new battery”.
You won’t damage the battery if you don’t code it to the car, but it may have a slightly shorter lifespan.
Coding becomes a bit more important if you replace your battery with a bigger, higher capacity battery, because a larger battery needs a higher charge profile to maintain at full 100% charge. Also some MMI systems can display battery info (state of charge etc) and may not display correctly if the battery is not correctly coded to the car.
iI you’re changing to a larger battery, or different battery type, you need to change more than the battery code, you also have to select the battery type and capacity. It’s easy to do with the likes of VCDS (other tools are available…) and all the info you need is usually on a label attached to the new battery, or you can just scan the QR code found on most new batteries these days
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Except that batteries don't seem to last as long as they used to. I'm seeing posts on here and other car forums where people are having to replace batteries in less than 4 years from new.
I've still got good batteries from cars I sold over 15 years ago........
One thing with "newer" cars is that their battery management system is not "bound" by BEM, and so I'm guessing that as this version of S3 is covered by Carista - as far I can see looking at the vehicle applications listing in my Carista app, that you will not need to mess about with any QR codes, just alter what needs altered from an exceedingly easy menu list - which was not quite the case for BEM'd systems.
I'd think that a lot of that is due to how people are using their cars in some way due to our change in lifestyle forced on us by Covid, my wife's car, a 2015 VW Polo 1.2TSI with its EFB is still surviving well enough, though changing the battery serial number seems to have "revitalised" it after I noticed a sudden step change in charging behaviour - for some reason, I bought a cheap 12V DVM that tends to live the 12V "ciggy lighter" socket, now I can't use either of my cars without that being present, strange but true, seeing is believing. So that means I currently have 2 new AGM batteries waiting to get fitted, both bought sooner than required!
Part of the reason that that battery and that of my car are still healthy will be down to how we use our cars and what we do to maximise battery life when they are not being used, ie CTEK chargers, though some people can't do that.
This just goes to prove that the supposed "intelligent" charging systems of modern vehicles are actually quite thick. The sceptic in me thinks it's deliberate manufacturer installed lifespan.
Yes, that 2015 VW Polo 1.2TSI's mileage was only 34ishK when that happened, I thought as there is a "charge throughput" counter in later battery management systems, that techs can read that as assume that a battery is "lifed" when that counter had reached a certain figure which is related to the battery capacity - I've forgotten the formula, but that 2015 VW Polo's charge throughput counter would not have been anywhere near that limit - unfortunately I had changed the battery serial number before reading and saving the battery stats, which was annoyingly stupid of me! The charging step change was from "normal" charging to 100% 14.8>15.0V constantly even if that battery had been recharged before the car was used, changing the serial number changed it back to a more sensible behaviour, ie almost back to only charging on demand and dumping charge into the battery on the over run. Now maybe I'm playing a "cat and mouse" game with this battery though hopefully I'll spot early enough when to replace it.
I just wonder how many other cars end up with their battery charging "switching" to 14.8>15.0V at all time and maybe that then reducing the battery life through over charging, well over charging in as much as a much higher constant rate of charging than these EFB batteries when used in a car with "regenerative braking".
I just wonder how many other cars end up with their battery charging "switching" to 14.8>15.0V at all time and maybe that then reducing the battery life through over charging, well over charging in as much as a much higher constant rate of charging than these EFB batteries when used in a car with "regenerative braking".
Well, 15 year old batteries is pushing it a bit, especially for cold morning starts.
I had to change mine in the S7 after 5 years. It was starting the car ok (but taking a few extra turns to get there) and I found that if it wasn't being run every couple of days the battery would be flat - I ended up buying a battery tender, but got caught out at long term parking at Heathrow and returned after a week to find a dead battery.
All sorted now though
https://audi-sport.net/xf/threads/new-battery-installed-s7.425082/
