Just waiting for my new battery to arrive, but started to think - how do I go about coding it in the VCDS? Does it need doing in all cases? I've tried to purchase the same spec of the battery, but some details are changed.

Old Battery:

Varta 7PO915105 AGM

12V, 68Ah, 380A DIN

680A EN/SAE/GS

New battery

Varta 570 901 076 AGM

12V, 70Ah

760A EN

So - new battery has slightly higher capacity (70vs 68) and higher max current (760A vs 680A). I am not sure about the nominal DIN rating that was 380A on the old battery.

First time I will be doing this, so would be great if someone could confirm which settings must be changed in the VCDS? Thanks!

If the old batter was 'coded' in as AGM (or "fleece" as VW call it) then that remains the same the battery, this setting is important.

Make or code is of no real importance that was just for VW's statistics and so they could make out a battery manufacturer was at fault for when VW messed things up (might is right) I think Varta was VOA in VW three letter/character code.

The "serial number" is important for system to know the battery is new and has been changed, as you see below often VW couldn't be bothered with it themselves at the factory and just put ten ones (1111111111) so you can if you want just change the last number to increase by one, so in example below to 1111111112.

You might as well change the 68Ah to 70Ah but do ensure you don't do what a professional auto-electrician was said to have done and put in 7Ah instead of 70Ah, why the VW programming allowed this is another matter.

I don't know the VCDS but here's some info from vrooom.

VCDS How to adapt a new battery.pdf

Below is from when a Briskoda member used an OBDeleven for the battery change on my wife's car, as you see I didn't even bother with the three letter code (I'm told Bosch (labelled) batteries are rom Varta).

If you want to know more about batteries and DIN and other standards of specification rating I can give you some info but generally don't be fooled by bigger numbers because it's a case of how long the battery can sustain any performance numbers in real world use. The CCA (Cold Cranking Amps) is about starting the cars in the cold which might be useful to you in artic bits of your country but generally modern cars can start the engines even when the battery state of charge is too low for the computer systems and programs and they throw up all sorts of unexpected warning light and messages and unseen error codes and unexpected issues. Often just fully recharging the battery properly can revive the battery rather than premature replacement.

Up to you what you do but if you change the battery, I personally always checked the battery is fully (100%) charged before I fit it to the car, not all batteries will arrive fully charged, an AGM battery may be at 12.4v on arrival but would be about 12.8/9v fully charged. Yes the VW computer program will soon do its own thing but I like to know that I start at 100% charged and will do a very occasional preventative recharge to 100% as it's good for the battery and its useful life, VW system goes to depending on who you believe 70%-80%.

HTH.

Edited 9 June, 20259 Jun by nta16
typo

Thank you kindly.

Regarding re-charging the battery, I have started doing this since winter, after the car was unused for some time and I tried to start it (without thinking!), I've got lots of random errors, and even message on the dash "please start the engine manually" (eeeehh?).

I have charged the battery, took a car for a drive, and all was fine. But then noticed that every now and then the car starting was a bit more difficult, so when I wasn't using the car for 2-3 weeks, I would charge the battery every now and then.

This week was the first time when the car wouldn't start despite being on a fairly long drive. It's a 2018 model, assume the battery is original, so not surprised it is failing...

Everything above written is true.

But there is always a "but".

My case - changed the battery to Exide last year. Garage coded the car with Exide dongle. But the charging voltage was always less than 13 volts instead of 14,8 as usual. Was not enough. Coded myself with VCDS. Exide code - fleece - 72 Ah. Nothing. Went to dealers, they recoded it again. Instead of Exide code there was a reading on VCDS, something "not this battery" or something like that, very ridiculous. But it started to charge finally.

So, change only the Ah reading and change the battery serial and should be done. But I suggest to buy some cheap ELM327 OBD device to monitor the charging just in case it wouldn`t go wrong as in my case.

And yes - AGM is not AGM on VCDS, always "fleece".

Edited 9 June, 20259 Jun by linni

Once the battery has been taken too low and or too often then it won't fully recover or has been taken to end of life, prevention is better than cure but of course the battery does have a finite life. 7 years ain't bad many (most?) wouldn't get that far and the newer the car the less likely.

The battery is very low indeed when it won't start the engine.

For your new battery if you're not using the car for a number of week you could either disconnect the battery or perhaps have it on a constant charger maintainer.

You may already being doing this but for other viewers as well - If recharging using an appropriate battery charger maintainer then follow the instructions in the car's 'Owner's Manual' and in the charger maintainer's instructions. Best is to recharge using a lower amperage charger (2, 3 or 4 amps) which will obviously take longer to charge and to fully charge the battery (to 100%), if this can't be achieve in one go then do it in two or three.

Batteries like 20c weather temperature and IIRC self discharge at twice the rate at 30c and twice as much more at 40c so it's not just in winter you need to be aware of battery state of charge plus of course in warmer weather the air-con might be used more that puts additional drain on the battery power storage.

Despite the car and it's charging system being older and of course getting older and more worn as time goes on if you look after your new battery, and that doesn't mean babying or any regular (very easy) work, then I expect you may well get more than 7 years out of it and good reliable service from it.

10 minutes ago, linni said:

Instead of Exide code there was a reading on VCDS, something "not this battery" or something like that, very ridiculous. But it started to charge finally.

This to me suggests the garage done something wrong when 'coding' (something went wrong). Data input error perhaps or procedure not done correctly (which you might be suggesting).

When dealing with the car's computer systems the tool being used needs to be appropriate to the make, model and (part) year (or VIN) and have it's program up to date before being used on the car and the car battery and the computer being used to 'code' both need their batteries at a reasonable state of charge, connections (wired or through air) need to be good and reliable, all otherwise spurious reports, readings or 'coding' can happen.

The car charging will not always be at 14.8v, new battery at good state of charge with very few electrics being used (other than those the car wants).

Checking after work has been done on the car is a good idea, and mistakes can happen with anyone, but checks needn't go on for too long.

See my previous post for what I and VW think about the description of "serial number" that part is redundant now AFAIK (and wasn't even used at the factory in 2015 based on my wife's car and others I've seen reported on Briskoda). If you are interested I can put up a VW pdf (available elsewhere on the internet) about this and stuff about VW batteries from when VW brought the stop/start shenanigans in.

I went to the official dealer and coding was done using ODIS. Will check tomorrow what the exact coding is there.

New battery is in, coding done. All went well, however....! I don't have battery tester (other than the VCDS when the car is running), and didn't think twice about connecting the charger to it first... Installed battery, and after little spin and coding it, checked some measured values .... strangely, the new battery was showing state of charge of only 75%, and usable capacity as 37Ah. Took it for a short drive around the town, and it charged up sligthly to 79% and 39Ah.

I think I will hook it up tonight and make sure it is fully charged, but I do wonder - should new battery arrive fully (or close to fully) charged?

Do also a full scan with VCDS and erase all the faults. Lots of things not working after the battery change unless you don`t clear these.

4 hours ago, rbss said:

checked some measured values .... strangely, the new battery was showing state of charge of only 75%, and usable capacity as 37Ah. Took it for a short drive around the town, and it charged up sligthly to 79% and 39Ah.

I think I will hook it up tonight and make sure it is fully charged, but I do wonder - should new battery arrive fully (or close to fully) charged?

8 hours ago, nta16 said:

not all batteries will arrive fully charged, an AGM battery may be at 12.4v on arrival but would be about 12.8/9v fully charged. Yes the VW computer program will soon do its own thing but I like to know that I start at 100% charged and will do a very occasional preventative recharge to 100% as it's good for the battery and its useful life, VW system goes to depending on who you believe 70%-80%

82Ah, you use a lot of electricity. 😄 Is that correct to the battery fitted (not 72Ah as in a previous post?).

For the sake of reassurance if I was a commercial concern I would leave the battery three letter code as VWŠkoda have it (JBC?) or use one of their other three letter/character codes (you had Varta? (VAO) and I would have have 1111111112 if it was 1111111111 from factory.

Perhaps the computer system objected to something there but with car use it settled itself, as long as the battery is an AGM and 82Ah(?) things should be fine but if you wanted to enter the (correct) three letter/character code for the Varta battery fitted and certainly correct the 82Ah if your battery is 72Ah, leave the battery serial as it is.

Edited 12 June, 202512 Jun by nta16
correction to VAO for VW Varta three letter code

I was remembered wrong, 82 Ah AGM is correct.

And yes, original one was Varta. Just a reminder - coding is done at official dealer.

Webasto consumes a lot. If there is -25 celsius outside, it needs at least 40 minutes to get car warm.

Edited 12 June, 202512 Jun by linni

I must admit I forgot you were outside UK.

In the England at least the Dealership doing any work isn't always as reassuring as it should be. As I put before much of the data entry for the battery is for the benefit of VWŠkoda rather than strictly necessary but again if I owned or worked for a Dealership or garage (not that I ever would) I would want to give my customers (who I'd not view as something I'd stepped in that wasn't cleaned up from being deposited on the ground) some reassurance by following factory protocol as much as possible. Perhaps "NOT" and "NoOESNorm1" are Dealership protocol(?) - as longer as the battery charges correctly via the VWŠkoda computer system and charging system that's all that really matters here.

I put an AGM battery into my wife's 2015 Fabia (even though it doesn't have the correct level of heat insulation for engine bay AGM fitment) and even though we don't often see minus Celsius and very rare double digit minus Celsius you may have seen I very occasionally fully (to 100%) recharge the battery with a "smart" (they are not) charger maintainer as the car gets lots of very short journeys.

Batteries like about 20C and self-discharge IIRC twice as much at 30C and twice as much again at 40C (we once had 40.2C where I live in England) so this needs taking into consideration too, plus of course in warmer weather the air-con is more likely to be used more.

Battery / charging issues are the number one cause of breakdown callouts in the UK it is very, very rarely a faulty battery but usually a charging problem or just driver/owner use / abused / neglect of the battery and the more modern the car (and to some extent owner/driver) the more likely "battery" problems. (I've put up various threads on this but can't remember how to get to them at the moment, slowly car owners are learning, and remembering, how important the car's 12v battery state of charge and health is to particularly more modern cars.

Good luck.

Hmmm, after hooking the battery to the charger, it was showing roughly 60% charge, so left it for few hours until it stopped charging. That was last night, just checked the car with the VCDS and it shows 88% state of charge, and usable capacity as 45Ah.... Car definitely starts much quicker, compared to the old battery (initial cranking was quite slow and engine was starting after 2-3 turns, now the engine starts almost instantly)

I wonder if these values are correct, or because the battery is connected in the car the values shown aren't totally accurate? not sure why the battery would have 45Ah compared to the 70Ah stated by the manufacturer ?

Need to go to another 300m drive tomorrow, hoping I'm going to make it :D

Edited 13 June, 202513 Jun by rbss

I'm a bit lost, did you charge the new off the car before fitting it to the car or charged it up after fitting to the car (following the instructions in the Owner's Manual and charger maintainer manual.

VW computer system only want to go to about 80% charge leaving room for energy recovery from braking to charge the battery, part of VW's pretence at more fuel saving and lowering emissions on large, heavy cars with over-sized wheels and tyres often only carrying the driver or one passenger.

Then you are trusting two computer systems for a read out.

On a modern car the battery is very low when it has difficulty starting the engine, by this time the car's computers would be moaning and throwing up warnings and unseen error codes and probably giving all sort of unexpected issues.

Before you connected the battery did you check the terminal post clamps were clean on the inside or clean them if required, battery terminal posts were clean, the terminal clamps were securely fitted to the battery terminal posts.

Have you checked the voltage from the alternator with engine running.

Do you have a constant drain like an added device to the car which remains switched for long periods when the engine (is and) isn't running.

Have you checked the battery 'coding'.

For some comparison, at 2-3 years old when I connect the 4-amp charger to the 60 Ah AGM battery in my wife's car (the one 'coded' on 25/6/2021 above) it took about 4-5 hours to top it up when it's wasn't really low and about 14-15 hours on a cold winter's night when it's was a bit lower but higher than most would bother to recharge it.

Fitted the new battery (checked terminals etc) into the car, and when I was coding it with VCDS I noticed that SOC and capacity was quite low - so then charged it with the battery in the car.

Took a car for a 300m drive yesterday, got back home safely, this morning was trying to start the car.... same story - car doesn't start, I will check it later on to see what the battery is showing, but I am guessing (with the stress on the word guessing), that the alternator is not charging the battery as it should ...

Just checked the battery with VCDS, shows 74% SOC and 50Ah usable capacity.... really puzzled now...

I've got video from non-start, but it's 17mb, need to find out how to compress it ....

You can check the battery/alternator charging with the VCDS but I'm not familiar with it I think it's a horrible legacy nerdy presentation system no doubt great for those familiar with it or experts with it. You can also use a multimeter to to check the alternator (and battery) well hopefully you can I've no idea if VW has made this overcomplicated on your model.

The sound of the car not starting in your video to me suggests other than a low state of 12V battery charge, something else inhibiting the engine start,but do remember I'm not an expert in anything. My first thought would be immobiliser system perhaps or these touch or proximity keys, their communication or batteries perhaps. You might be better getting a full report off the VCDS to post up in the 'VCDS & Diagnostics' forum of Briskoda for VCDS owners to look at (one computer thing can affect one or more other computer things).

Doesn't matter on last video but for future photos and videos holding the camera/phone/device for landscape and not portrait generally gets more useful information on to the image. There's also some sort of lock and message showing on the dash but too blurred to see.

You could also look and search this forum to see if other Kodaiq (particularly 2018 perhaps) owners have had similar engine starting, battery or battery charging problems.

ETA: always consider there might be more than one issue at play and finding one might not resolve all.

Edited 15 June, 202515 Jun by nta16
ETA

Thanks Nigel - I have checked the VCDS again for errors and there is was a few (report attached) - one about NOx sensor, but also stored fault about low key battery and fault of the steering assist system.

I have replaced key battery, and car started 3 times, but I am not sure if this is truly the end of it ... It's really annoying that it's an intermittent issue, so even more difficult to diagnose...

And as usual, we're 2 weeks away from long trip to Poland, and the car starts making tantrums ....

Preview attachment Log-TMBMK9NS6J8047143-162004km-100664mi-15052025.txt

Log-TMBMK9NS6J8047143-162004km-100664mi-15052025.txt

49 KB

Take it to the dealer and let check the battery management system. They tend to fail on VAG cars.

Thanks Linni, will try that, hope there will be a slot available before I need to go to EU .... Will also give the guys at Fife Autotech a call, and see what they say...

Sod's Law that the car plays up at inconvenient times, I used to run old (and brand new) English made cars and had it happen so many times.

Sorry I don't do Google GMail stuff other than searches, not that I know anything about VCDS and reports other than looking at obvious stuff, others will know if there's a widget/digit/code out of place but not me. Other upload VCDS reports to their posts in I guess some sort of MS document or image, I'm just cut/ copy 'n' paste, jpg image/screenshot or pdf file, computers annoy me too much to do much more, I can't stand their inconsistences and failings, had too many decades of them.

If your 12v battery is/was low all sorts of odd error codes can show, once you deleted them and sufficiently recharged or replaced the 12v battery and perhaps driven for a bit most of those errors might not return, those that do you check out.

Key batteries can be a bit of a pain even when replaced and this KESSY type stuff is just another layer of potential pain (I like a metal keyblade and that's preferably no alarm or electronic immobiliser. Where do you keep the second key?

You should never regard it as the "spare" key but use it in some sort of alternation with the other key, that way you know the batteries are good, where to find the second key ("spare" keys are often mislaid, lost or possibly flat battery) and if with keyblades more even wear on keyblades and mechanical locks.

Is there any synchronisation with the car to be done after changing key battery, if so did you do it?

What was that blurred white lock like symbol and message below on the dash about, what does it mean or relate to?

That's me out of ideas.

You might not be able to get your car into an available slot at the Dealership before you go away, I would check first thing tomorrow if that's what you want.