Hi All,

I’ve had a search for the answers and as yet unable to find them so i hope it’s okay to ask them here.
The car in question is a A6 2.0TDI diesel 2011, after the car has been stationary for a couple of weeks and what with the cold weather the battery is low and now only give around 5v. Putting the battery on a CTEK optimiser for a few days it run though the first two modes that given an error at the third stage reporting the battery won’t take a charge.

I’ve settled on a replacement battery is required and checked and sourced the matching model (H15 Varta Start-Stop Plus AGM Car Battery 12V 105Ah), i understand that the battery needed to be coded to the car using the details from the new battery, if i swap the batteries over will the car run before it’s coded? is the coding to help with the battery conditioning / management?
With the existing battery being so low (no electrics on the car at all) is there a chance of other problems such as key coding?
Just trying to prepare myself for what may happen and needs doing after the battery is replaced.

Thanks in advance.