IknowHuhA6

I reviewed the service manuals and no mention of vagcom is mentioned. Can you please post where you found this requirement to make sure the right information is researched. The internet is full of false, half truth, and full truth. Little more investigation is needed to reduce speculation and opinion.

Also, i'm invested to know for sure since I will be replacing my battery in next couple of months. I replace my batteries every 4 years regardless of other variables.

Thank you.

SSA6

I got my information from this thread on our forum:

https://www.audiworld.com/forums/a6-...ry-qs-2886106/

uberwgn

From what I've seen, many of the cars sent to Ca receive an AGM battery. My original battery was not AGM, however, the replacement is.


My original battery wasn't giving any visible symptoms/issues, but it showed it was progressively getting weaker (quickly) on the battery meter in the MMI regardless how much or how long it was charged for. I didn't realize the BEM had activated 'til I went in and scanned when I re-coded the battery. The scan showed a single BEM activation maybe 1 month earlier.

uberwgn

There are so many threads on this that it becomes painful to repeat over and over.


A battery obtained from the dealer will have a code which is supposed to be entered with VCDS or whatever the dealer's equivalent is called at this time. Dealer cost for battery replacement: ~ $350


A battery purchased from the local auto parts store will not have this code on a label stuck to the outside of the battery. So, people have gone in (via VCDS) and changed their existing code by one character to alert the BEM that a new battery has been fitted. Cost for appropriate battery at local store: ~ $180


There is a long thread on this subject on AZ.

IknowHuhA6

Thank you so much for sharing. Since you've already looked this up I do appreciate the help to learn from what you've already found which I was unable to find.

I can sympathize with your viewpoint as I've been there myself in having to repeat information over and over. However not all of us have the vast experience and skills of the veterans as yourself. Whatever the reason for our lack of understanding ...I can understand the frustration.

Your reply was very helpful and greatly appreciated. I can respect the vast knowledge you have brought to the forum prior to my joining.
Thank you, and apologies for my ignorance.

redrocker55

My 2010 S4 battery lasted 5 years and 150,000 miles which is when I sold the car. Battery still started strong, even in very cold temperatures.

I always thought heat was a battery killer (part of the reason we see so many cars today with insulation wraps to keep heat out or battery locations away from engine...my wife's SUV battery is under the passenger seat, my C7 in trunk) and cold weather amplifies a batteries weakness.

uberwgn

Redrocker, did your car have an AGM battery? We got what I'd describe as extreme life out of the OE AGM battery fitted to our Avant. IME, the AGM batteries, under good conditions, will last up to 50% longer than a traditional battery.

redrocker55

I agree on AGM batteries. The are worth the extra money.

The battery in my S4 that went 150,000 miles was original equipment standard issue lead acid sealed but not AGM. The battery in the S4 is huge though. It was bigger than what was is installed in some SUVs I have owned in the past.

NoVA_A6

If you have a battery that was just disconnected do you have to recode it?

The reason I ask is when I bought my 2012 A6 this summer I had the car shipped and either the battery died or they disconnected it. Once it was charged all the error codes went away. Recently I had an issue with my sunroof switch looping the sunroof open and closed no matter which position it was in. Scanning it I get error code 01512 - Control Module.
From what I've been reading others have had this issue when they've replaced the battery.

uberwgn

No, on the re-coding following a disconnect.

Nova, can you clear the faults with VCDS (or get your local person to do it for you) and see if that corrects the problem you're seeing?

I've seen memory settings lost on the windows, sunroof and seats when power is lost on other cars. I would ensure your battery is solid, clear faults and take it from there...