Battery Drain (don't want to hijack Oli's thread)
 

Hi peeps,

I am aware that Oli has his own battery drain problem and I will be following some of the suggestions there so as to see if I can find problems on mine, but I didn't want to hijack his thread.

Essentially over the last couple weeks I am getting the "Battery Low" warning and it says it will charge the car while driving, it never seems to charge it enough. I have put the car on my CTEK a few times, first to do a battery condition cycle, then after to charge, its actually charging now as she struggled to start this morning.

I have had a few niggling errors so far come up, i.e., the boot wont open with the motor, sometimes wont close with it either, however, If I had been driving or the engine is running, it works absolutely fine, also the same after a battery charge. Which leads me to believe its battery related. I have also seen very intermittent adaptive lights errors and ESP errors, but each only once, which again makes me think its power related as they disappear after a run or a charge.

This morning I turned the car on to see a new error on the dash, the yellow suspension level light, however, once the car went on the CTEK, the light disappeared.

I suspect that my problem isn't a bad battery as I had it load tested by the auto electrician who was working on my track TT loom, and he tested the battery with a load and it stayed at 12.1v

Being as all this is guesswork as I only found out this morning that my VCDS lite and dongle don't work on the S8, I haven't had to scan her for anything all year, but now I can't provide any scans - until tomorrow that is as I have just bought a full version from Gendan this morning, so I know I can scan it then and post up what it says.

I will put the car into jacking mode when the battery is charged later and see what happens, anything else I can check at the moment before the tool arrives?

Thanks

Shouldn't the good condition battery read something like 12.6x Volts ??
12.1V seems a bit to low.
Battery on the S8 had this sort of readings and I was experiencing similar issues so I got new VARTA battery and since then all problems has disappeared.
http://www.ebay.co.uk/itm/Varta-I1-V...YAAOSwojRYSoKQ

Some D3s had issues with the battery management ECU which is in the boot by the wheel arch above the (-) terminal. Can't remember is software update solved was the way to go or just replacing it with a later part number module.

How about changing the last digit of your battery serial number to make ECU think it's a brand new battery in case someone messed around while your car was off road with the gearbox issues for a while?? Unlikely, but worth a go if your battery is still original which means it is kind of due a replacement.
And I say that because on the A8 I've had a good battery, no issue prior or warning light/errors etc and one morning battery has completely died, not even a drop of juice left to do anything and car was driven day before.

Hi Marcin, thanks for the reply, I didn't know my car has been off the road with a gearbox issue? certainly not in the time I have had her, she's been good as gold - was this something that happened with a previous owner before I bought her?

Is there a way to find out if its the original battery?

I've bookmarked that battery, I'll check out the voltage reading with VCDS when it comes and the battery is charged to get a proper accurate reading. Is there a guide anywhere on how to code a battery or change the number? quite new to VCDS aside from the usual clearing of DTCs on my TT

Thanks

Crap...Sorry, that was Turbo Tony's S8, sorry :hammer:

Original battery will have a white label stuck on top of the battery with Audi logo, part number and other info, about 3x3 inch size.

Follow this guide from Ross-Tech and change just the last digit in the serial number box for new battery.
http://wiki.ross-tech.com/wiki/index...ry_Replacement

No worries mate, I have posted on his thread a few times...

So, the plot thickens - I checked all the old receipts I got from Duffy when I purchased the car, and there is a receipt for a Bosch S4 110 Battery in his name, dated 27/04/2015, however this is what is in the boot:

http://i1092.photobucket.com/albums/...ps54x3z1rg.jpg

http://i1092.photobucket.com/albums/...psmc6mxz8c.jpg

http://i1092.photobucket.com/albums/...ps3ui0cysi.jpg

So my guess is he put the old battery back in when he sold it? I really can't think of any other explanation to it, seems odd, but I think based on what I see and what's happening a new battery is required.

That link you posted, is that the same one you bought? I only ask because I used the eBay parts checker and it said it doesnt fit my car?

Well, this is the original battery so I would start from changing the battery because when mine died one morning with no warning at all it was the day I really was in the rush and needed the car.

Yes, I have this battery fitted in my S8 at present +++
Same size, same spec apart more amps, 920 instead of 850.

I fitted Bosch S5 to A8 and had no issue either, but this time I wanted same brand (Varta) for whatever reason which I can't explain :rolleyes:

I have a varta AGM stop start battery of the largest size they do and it's been bulletproof.

http://www.varta-automotive.com/en-g...ic/605-901-095

Battery ordered, thanks peeps, tomorrow I should have a new battery and full VCDS, so I will update this thread with my findings.

Appreciate the help & responses +++

my thoughts exactly, I can't see any other reason for there being a receipt for it, but an old battery in the car thats totally different?

That was nice of the seller if they knew the old battery was buggered (or why else replace it? ) and didn't even bother to tell you... :tuttut: