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installing new battery on 2015 will require coding

92683

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socal.
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2015 s3
#1
i recently installed a brand new battery and now i need to code the car to have it recognize it.

you can use anything else on the market that will work but for this, i am using ross vcds.

i found some useful videos on youtube and ill link them as i refind them.
the first best one is from deutsche auto parts video.

reasons:
- you want to do the coding so the car will recognize that you have a new battery.
- as the battery ages, the ecu will tell the alternator to pump more power to your aging battery have it topped off as the years go by.
- if you don't, the overcharge will damage your new battery in a few weeks to a few months. you will not notice it as much if your outgoing battery is not as badly aged.
- in my case, i noticed my new battery starting to overheat. i mean it was hot after driving only 35+ miles. it wasn't hot because the engine area was hot, the battery got un-normally hot. i was able to turn it off and remove it quickly.

for the coding, i now understand what needs to be done. the coding is not as difficult as it seems.
since the dealership plugs it into their system it automatically fills in the spaces with predesigned letters and numbers but when i do it on vcds it can be anything but it doesn't mean it will accept it.
the goal here is to just reset the battery section in the ecu. to do this all we have to do is to "flip" the internal ecu "switch". so by having it accept a new coding - any new coding- it will reset itself.
so when you code it really doesn't matter what you type in as much as the ecu just needs to be able to accept the format you type in.
some people have just put in the new battery serial number, branding, and type of batter but in the right format.
another person said they just put a bunch of zeros "0000000000" (ten zeros) or a date that they installed it in and it works. remember the format is the key. it doesn't matter if you put in the right amp-hour or anything. all i can tell is that these areas is like windows "notepad" it just takes in notes for you and lets you remember what you installed.
once you do all this and the system accepts it, your ecu will reset and your alternator will then start at a lower recharge cycle. with all that, the only caveat is that i do feel if you have the AH number, put that in.

- during my research i read what the reset does is, it then lets the ecu sample a bunch of info to make sure the alternator will pump out the right charge after the reset cycle. so basically when we reset it, we are essentially letting the ecu turn on its sensors to know how much energy the new battery needs. so we really don't need to input correct values really.
what the ecu is looking for are these - if not not even more than these parameters - "trigger events“ (impulses, signals e.g. starts, cold starts, cycles)

when you configure vcds or use anything else, you will see the BEM sticker information requirement. but you don't have to use it if you have an aftermarket battery. why i say this is because almost every video you watch or every posts you see about coding in the BEM, almost everyone tweaks it or have their version of inputting the information here. well my conclusion is that it doesn't matter the info but rather the format. once the ecu takes it, it will start the reset cycle.
the BEM is just the info coded on the OEM batteries audi sells. aftermarket doesnt have it. i personally went with a braille lithium battery and it clearly doesnt have this sticker. but if you understand what this does you'll will see why its not important.

" What actually happens when the BEM code is entered?
Entering the BEM code does nothing other than reset the configuration or actual values of the old battery stored in the control unit and save the current mileage. it will trigger the ecu to start to relearn as well, like i mentioned before.
again these triggers are (impulses, signals e.g. starts, cold starts, cycles)
https://www.bannerbatterien.com/en/...TO-Correctly-registering-start-stop-batteries

if you go lithium the newer cars 8v and up do have a selection for lithium for a battery type selection table. for my second car (an 8p model) it does not have this as a selection when i go through vcds. again i don't think having this option or not is important to allow the ecu to flip/trigger the switch on the reset. it will happen if you just code in something that the ecu accepts.
* coding in and accepting is the trigger reset.

video link;

 
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OP
92683

92683

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Staff Team
Messages
392
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City
socal.
State
CA
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What I Drive
2015 s3
Thread Starter #2
i just found some good general info on lithium batteries. things you can do, things you should do, and things you cant do to lithium batteries.

lithium facts and care info
 

ViperG

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2016 Viper Green S3
#3
i just found some good general info on lithium batteries. things you can do, things you should do, and things you cant do to lithium batteries.

lithium facts and care info
Haven't see a gas car that uses a lithium battery. Also let me pop in an article from obdeleven a cheaper option for people to recode their battery or switch types.

https://forum.obdeleven.com/thread/2041/battery-replacement

That's an interesting battery that you picked up didn't realize they were making them. Not sure how I feel about lithium that doesn't have a cooling system.
 
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