Advice on replacement battery

[HDPete]

My battery is just over 4 years old. The car threw an MIL light last week. After checking the codes they were all low voltage related. I then conditioned the battery with my Ring charger which got to 60% but then reported F05, which is where it can’t maintain the battery. I do short trips mainly and the auto stop start never works.

So it’s looking like I need a replacement.

I headed over to Euro Car Parts and found they suggest a battery that’s £500. Surely that can’t be right?

Is there a general consensus for which battery size, make and cost?

Cheers
Pete

[morski]

£500 is way off. Dont even think about it.
Your original battery will probably bee either a 95-110Ah battery and even a genuine one from Audi/TPS will cost from £210-£235 inc vat and a similar one from a reputable battery place should be £150-£175.
Make sure you get an AGM for the stop start system and any big brand ie Yuasa,Varta, Bosch etc will carry a 4+year warranty.
Also if you have VCDS you will need to code the new battery to the car in the CAN gateway just so the car knows that the battery has been replaced and can apply the correct charging etc

[HDPete]

Fantastic! Thanks Morski. Is there any guidance on where I need to go in VCDS to do that?

[don0301]

I recently had to replace the battery on my C6 RS6, I had been using a CTEK to maintain the battery but this year has obviously affected it.

Mine uses a non-AGM 110A 020 battery. Although an AGM battery is also recommended for my car!

A quick google search found a non-AGM VARTA battery with 5 year warranty for £109.50, a pleasant surprise! the AGM version was £195.

If you go to the VARTA site and put your car details in, it should show you the correct spec battery to get, if you can't be arsed looking at your battery yourself.

It will also point you to retailers, but I found cheaper online.

Since the new battery fitted, several voltage/current anomalies have disappeared in my VCDS.

I couldn't get any info regarding battery code, I just changed the code with VCDS by one number, all sweet.

just google VCDS battery code should point you to the procedure on your car. Straight forward. Just make a note of the old code just in case.

[morski]

This is from the Ross tech site: http://wiki.ross-tech.com/wiki/index.ph ... eplacement

[MountainMutant]

Where is the battery? My old C5 was in the boot floor but I have the air suspension on my car and no battery there.

[morski]

Its in the boot. Air suspension tank is bolted directly in front of battery or behind depending on which way you look at it

[Tadass910]

I am on original battery from 2014 April still running fine

[Lig]

Hi hdpete,

No coding required... have a look at this thread...

viewtopic.php?f=76&t=132632&p=919953&hi ... ry#p919953

Cheers,
Lig.

[HDPete]

Thanks Lig!

[morski]

These cars have a battery monitoring control module fitted to the -ve terminal that monitors its current etc so he new battery will need coding to the car. Simple process.