How complicated is it to replace the battery on a B8 A4?

**tilhas** · 11-24-2011 06:05 AM

How hard is it to replace the battery on a B8 A4?

I googled it and some people say you have to code the battery?
My battery died and Audi wants 350$ to install a new one. Where I could buy it from parts for 135$. Makes no sense to pay 215$ for someone to just put a battery in :crazy:

**tilhas** · 11-24-2011 08:49 AM

I found I needed to code the battery and that can be done with VCDS.

Any instructions on how to remove the battery?
I know it is in the trunk but anything special I need to do like keep a power source so the battery never dies etc etc?

**tilhas** · 11-28-2011 02:39 PM

Should I put an Audi 380amp battery or an interstate 955 amp battery (I'm told it is compatible by a tuner shop that would do the install)

http://www.interstatebatteries.com/c...nths+-+765+CCA

**ExhaustNote** · 11-28-2011 02:46 PM

Curious why you keep asking this in the A5/S5 forum instead of the B8 A4 forum...

**Beast** · 11-28-2011 03:55 PM

^wonderin the same

**tilhas** · 11-28-2011 06:10 PM

Posted it in the wrong form, i'll ask a mod to move it.

**tilhas** · 11-29-2011 07:08 AM

bump

**MilesM** · 11-29-2011 07:18 AM

Open your trunk, go into the spare wheel compartment, take the spare out, and it's in that container underneath the spare

**coolwater** · 11-29-2011 07:45 AM

How long/miles did you have your B8?
Curious if your battery died of old age or some other fubar.

-cW

**tilhas** · 11-29-2011 01:38 PM

Car had 60,000 km

**tilhas** · 11-29-2011 02:09 PM

This is how I changed my battery on Audi A4 2009 (B8)
You may use this as reference only. I am not a mechanical, electrician, Audi/Vw mechanic, etc.

Note: Coding the battery did not seem to be required in my case.

Step 1, open your trunk and use the latch to open the cover.

Step 2, Unscrew spare tire and remove.

Step 3, Remove plastic cover

Step 4, Remove tool holder and tools

Step 5, Remove Spare Wheel holder using 13mm socket.

Step 6, Remove Battery Holder using 13mm socket.

Step 7, I don't know my radio code so I connected an Aux battery to the trunk to keep power in the car. NOTE this is not safe as when you remove the battery the Positive is still LIVE so make sure it doesn't touch the body or yourself!!

Step 8, Remove battery cover, by just un-clipping the two bottom sides

Step 9, Use a 10mm socket, to loosen battery terminal clips.

Step 10, Remove Black Hose into Negative side

Step 11, Remove the Positive and Negative. Make sure they don't touch and the Positive does not touch the car body!

If coding is required the serial # is engraved on the battery and brand is on a sticker on top of the car.

Step 12, put battery in and unplug batter in hood if one was connected.
Reverse what order of how you took out old battery.

Turn on car and drive for a little bit. In my case I plunged in VAG and erased all the errors (low voltage errors)

Did I miss anything?

**Turbo Freak** · 11-29-2011 04:33 PM

Step 7, I don't know my radio code so I connected an Aux battery to the trunk to keep power in the car.

I do not believe that this is required on a B8. Last spring I disconnected the battery in my car while I was installing a sub amp and I did not bother with this and the radio worked just fine when I repowered it...

**cory_can** · 11-29-2011 04:39 PM

I've disconnected my battery several times for various installs and there was nothing lost or nothing that required to be (re)coded ....other than putting my APR tune back from stock using the cruise stock

**DavidB8** · 11-29-2011 04:50 PM

I to have dissconnected my battery more than a few times and never needed a radio code. However there are lots of codes in VCDS so I clear them. Although over time they will clear themselves.

**tilhas** · 11-29-2011 06:16 PM

I think my car still thinks it is in power management safe mode because my battery level on MMI is not there.

I'm going for a drive now and come back we will see if that changes the issue.

**tilhas** · 11-30-2011 07:41 AM

I drove 30km highway yesterday at 120km/h and the battery level on mmi was still grayed out.
Today after driving to the train (all city). MMI pops up at 50%!! I pull out my cable and check it out.

Looks good?

**simplicity** · 11-30-2011 03:39 PM

Did you end up replacing with OEM or the Interstate?

**tilhas** · 11-30-2011 10:15 PM

OEM, 135$ at the dealer.
I don't want to mess with my warranty. I've got it till 2015.

**rippin'av** · 12-01-2011 03:58 PM

Yeah, I had the same questions when the dealer told me my battery was no good anymore. How can it be $350 just to replace a battery I thought? Apparently you need to tell the computer it's a new battery or else it will continue to charge it and treat it as a bad battery and eventually kill your new battery. I complained enough that they charged me only $200 for battery including install. I still think it's crazy that you can't just swap out an old one for a new one.

**tilhas** · 12-02-2011 06:02 AM

I couldn't find a place to code the battery. I hope i am not going to kill the new battery.

MMI now shows 100%. I'll check with the computer later today to see what it says.

**tilhas** · 12-02-2011 06:03 AM

I couldn't find a place to code the battery. I hope i am not going to kill the new battery.
I'll bring out a multimeter and check the voltage. If over 13V it's charging right?

MMI now shows 100%. I'll check with the computer later today to see what it says.

**jabicho** · 12-26-2011 12:51 PM

Hello again,what happened in the end? did you have to code it???

**tilhas** · 01-30-2012 06:22 AM

Car still works perfectly. Never coded it.

**jabicho** · 01-30-2012 06:32 AM

Good to know that, thanx for replying

**EuroEclipse** · 02-07-2012 07:57 AM

I'm in the same boat if you look at my Chatterbox thread. I've never heard of coding for the battery, though. I just checked with the dealer here in the area. They said they hook it up to a battery tender just in case, but there is no coding that needs to be done.

**wrclaguna** · 02-07-2012 12:07 PM

I changed the batteries at home and later had to code the new battery .
You must enter a so-called. BEM code with a sticker which is on the battery

**Ryan_T** · 02-07-2012 12:45 PM

Thank you for all this. My battery is starting to die too. It's disappointing after only 3.5yrs.

**tilhas** · 02-07-2012 05:51 PM

Originally Posted by wrclaguna

I changed the batteries at home and later had to code the new battery .
You must enter a so-called. BEM code with a sticker which is on the battery

What year is your car? mine is a 2009 maybe that's why

**wrclaguna** · 02-07-2012 08:06 PM

Mine is from 01 2009 Battery Indicator poazywal 10%

. One fine day at the start just syanął, by the way broke the ignition. It was difficult to insert or pull out the key also I went to the exchange

**headac56** · 02-17-2012 02:12 AM

Tilhas,

Fantastic write up - better than Elsawin.

Positive information from Banner Batterien suggets that the B8 will "learn" that a new battery has been installed ->

http://bannerbatterien.com/banner/fi...echnik_GB3.pdf

Did you get any later problems because you did not use a BEM code please?

**tilhas** · 02-19-2012 07:52 AM

Originally Posted by headac56

Tilhas,

Fantastic write up - better than Elsawin.

Positive information from Banner Batterien suggets that the B8 will "learn" that a new battery has been installed ->

http://bannerbatterien.com/banner/fi...echnik_GB3.pdf

Did you get any later problems because you did not use a BEM code please?

Only thing I did was I reset all DTCs with VAG COM cable and I never got any errors after that.
Note I have a 2009 thou, maybe the 2010+ with the stop/start and energy efficency program require the battery to be coded.
On my 2009, my car has been running perfect since I've put a new battery in.

**tilhas** · 03-10-2012 12:22 PM

Update:
In VCDS
61-Battery Regulation module
Would never work.

I'm having some weird electrical problems so i decided to revisit my battery
I went here
VCDS (screen 19-CAN@gateway _> Long Adaptation -> Channel 4 -> Battery identification)

and my battery was ENERTEC and an Engraved # 01939117

and in the back there was a QR Code and a # beside it

Decoding the QR Code I got
205# 000 915 105 DH #0803800 #588119201#27081134*205 EMC318R25U/*= 99{40@85m
So in VCDs I figured the first # is the Part #, 2nd is manufacturer of the battery and 3rd is the serial#

Before
8K0915105D MLA 180714EPDD
After
8K0915105D MLA EMC318R25U

I don't think I'm suppose to be MLA I'm suppose to be ENE for ENERTEC but it won't accept 8K0915105D ENE EMC318R25U.

Am I doing this right?

I saved it and the car seems to be running fine.

**wrclaguna** · 03-15-2012 11:45 AM

The new battery at this point there is a BEM code.

**tilhas** · 03-16-2012 06:23 AM

Originally Posted by wrclaguna

The new battery at this point there is a BEM code.

I looked all over my battery and didn't see a BEM code, I thought it was the code under the 2D bat code. Can you please take a better picture of the 2D QR code and post it in the decoder. http://www.patrick-wied.at/static/qrgen/
I'm curious to know if the BEM was one of the codes generated.
Thanks.

**Point.Blank** · 03-29-2012 12:46 PM

anyone know how to take the nut and bolt off of the (-) terminal? I know you can force the nut off but can you also force the bolt off? Im trying to change the nut and bolt with one that I can actually use correctly.

**Point.Blank** · 03-29-2012 02:23 PM

Seriously fuck the battery terminal.. My hands are bleeding in many different spots and i still cant get this fucking nut off this bolt. Haven't even been able to tell if i can get the bolt out. Extremely heated right now

**BMWBig6** · 04-18-2012 07:04 AM

Originally Posted by headac56

Tilhas,

Fantastic write up - better than Elsawin.

Positive information from Banner Batterien suggets that the B8 will "learn" that a new battery has been installed ->

http://bannerbatterien.com/banner/fi...echnik_GB3.pdf

Did you get any later problems because you did not use a BEM code please?

So according to that reference, the car should "learn" that a new battery was installed and adjust accordingly, right? Do we know if this applies and truly happens with B8's, or is the BEM coding required to tell the car a new battery has been installed?

This is the relevant portion of the bulletin posted above, but it talks about the A6 model:

Self-teaching system
In the case of an elderly battery, the vehicle system stores the term “defect battery”. Accordingly, if a new battery is installed without the entry of a BEM code, initially the vehicle does not recognise the presence of a replacement. Therefore, the energy management system must either be informed of the new battery status via a BEM code input, or learn the new battery status. The more trigger events (impulses, signals, e.g. starts, cold starts) experienced by the battery, the faster this process is completed. The vehicle computer then successively releases the previously limited systems, e.g. the full performance of the air conditioning system.

**SDF1** · 04-18-2012 09:19 AM

It looked like the car did learn on it's own but when i brought the car in for a weird electrical issue, the dealer knew right away that the battery was not programmed. So i quickly programmed it, didn't see a difference.... althought my alternator died a couple of weeks later.