New Battery Installed S7

RAF_S7

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Over the last couple of weeks Ive found the (2016) S7 taking a bit longer than normal to start from cold, not a lot longer, but long enough to be noticeable, and after a week of being parked up it would really struggle - or just not turn over at all.

Did a check using VCDS, and got the results shown below, which were low enough to trigger a new battery purchase (The car had been driven for a couple of hours the previous day, tests were done from cold, with ignition on and engine off)

Screenshot 2021 03 31 at 152451

The original OEM battery was a Varta AGM, 92Ah and 520Amp (OEM Code PR-J0B), and as I leave the car of long periods when Im working away, decided to fit the largest battery possible.
The Varta AGM 105Ah and 950Amps was sourced online (a UK eBay seller, and over 50% less than Europarts etc.!)
You can see the physical difference between the two batteries below. (And yes, heavier!)

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Installed in the car.

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I also decided to fit a remote battery monitor, and after hunting around on line settled for this Bluetooth connected device from Amazon. (You can search for it using "Auto Battery Monitor BM2" - under £26 :icon thumright: )

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This is a screen shot of the top level menu of the battery monitoring App. Lots of useful info - that doesn't need VCDS!

Screenshot 20210331 155344 Battery Monitor


The larger battery combined with the already packed S7 boot, with its suspension air-tank, combined with the shortish leads on the monitor meant it had to be mounted on the air-tank using double sided sticky tape. Note the -ve terminal secured to the air tank as it wouldn't fit under the battery cover!

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If you have access to VCDS (other diagnostic systems are available...) go to Select Control Module-->19-CAN Gateway-->Advance Measuring--> then check/tick the boxes relating to battery from the long list on the right hand side (You can ignore Battery 2 as not applicable to UK vehicles)

Cheers,
John :thumbs up::racer:
 
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Great write up and tip ont he bluetooth monitor. Cheers for that

I'm about to replace the battery in mine but do not have BEM code on it. Replacing Bosh acid one for larger Bosh AGM one.
Searched online and all pointers are for coding using BEM code.
Any tip with VCDS to code the battery without BEM?

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Great write up and tip ont he bluetooth monitor. Cheers for that

I'm about to replace the battery in mine but do not have BEM code on it. Replacing Bosh acid one for larger Bosh AGM one.
Searched online and all pointers are for coding using BEM code.
Any tip with VCDS to code the battery without BEM?

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When you go into VCDS there are entries for Battery #1 & Battery #2. You only have to code Battery #1. #2 should be left uncoded.

Two out of the 3 fields are drop down menu’s, and pretty self explanatory so you shouldn’t have an issue. There is no specific AGM coding to be done.

The battery serial number can really be anything, including just changing one digit from the existing entry.

If there is no recognisable serial number visible on the new battery, I found scanning the QR code actually popped the serial number.

John :hi:
 
When you go into VCDS there are entries for Battery #1 & Battery #2. You only have to code Battery #1. #2 should be left uncoded.

Two out of the 3 fields are drop down menu’s, and pretty self explanatory so you shouldn’t have an issue. There is no specific AGM coding to be done.

The battery serial number can really be anything, including just changing one digit from the existing entry.

If there is no recognisable serial number visible on the new battery, I found scanning the QR code actually popped the serial number.

John :hi:
Cheers for that.

Had a go at it last night and QR was there with Bosh code together.
Alhough my new battery was 95Ah and 850A, found OEM varta battery with 92AH 850A picture on my phone and used same coding. Accepted all and from 1 bar battery meter on MMI went to full.
Had a nice drive around and all hunky dory.
Fingers crossed I will have no future problems
69c96b0119d991c3579196c700640a45.jpg
a804930d719ba6ceb41d165a0056b454.jpg


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Cheers for that.

Had a go at it last night and QR was there with Bosh code together.
Alhough my new battery was 95Ah and 850A, found OEM varta battery with 92AH 850A picture on my phone and used same coding. Accepted all and from 1 bar battery meter on MMI went to full.
Had a nice drive around and all hunky dory.
Fingers crossed I will have no future problems
69c96b0119d991c3579196c700640a45.jpg
a804930d719ba6ceb41d165a0056b454.jpg


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I'm surprised there was no option to code in a Bosch battery:readit:

The issue with coding it as a 92Ah instead of a 95Ah, is that the battery meter on the MMI will likely not report correctly. The battery charging systems on these cars is fairly sophisticated, so you may find that the charging system thinks the battery is fully charges at 92Ah - and not charge all the way up to 95Ah. Worth keeping an eye on, just in case you get any further issues :racer:
 
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I'm surprised there was no option to code in a Bosch battery:readit:

The issue with coding it as a 92Ah instead of a 95Ah, is that the battery meter on the MMI will likely not report correctly. The battery charging systems on these cars is fairly sophisticated, so you may find that the charging system thinks the battery is fully charges at 92Ah - and not charge all the way up to 95Ah. Worth keeping an eye on, just in case you get any further issues :racer:
Could not find any pictures online for OEM Varta battery with same values to code in.

You are right about the battery not fully charged to the manufacturers capacity.
Could that have a major or any impact of the life of it, you think?

Copared old battery with code in vcds before new one installed and it was as JCB but none of the details from the code matched old battery.
Think code used in old coding was also taken off the net and didn't wanted to risk I put anything wrong with new one.

Thank you for all tips

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Could not find any pictures online for OEM Varta battery with same values to code in.

You are right about the battery not fully charged to the manufacturers capacity.
Could that have a major or any impact of the life of it, you think?

Copared old battery with code in vcds before new one installed and it was as JCB but none of the details from the code matched old battery.
Think code used in old coding was also taken off the net and didn't wanted to risk I put anything wrong with new one.

Thank you for all tips

Sent from my VOG-L29 using Tapatalk
I don’t think the 92Ah coding will have a significant impact on battery life :icon thumright:
 
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I’ve recently changed batteries in the RS3 for similar reasons.

New Varta was a little bit more than the oem JCB Varta 80ah vs 75ah
However it’s been perfectly fine since change over and standing voltage is a steady 12.6 v now, before it would drop to 11.80v.

cfbbe6a27803dbe07a8a8edc7eb9fe54.jpg

d3c0a54e59fff70641785bb833b690b5.jpg



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