Mother in law's 2008 v8 touareg battery died and was replaced recently. This is the second replacement in the last 2 years. After the most recent replacement the car will start a couple of times and then not start at all. The battery has to be disconnected and reconnected and it will start right up. This has left her stranded multiple times. I've tried my vcds but it is not compatible (2014 passat tdi). Any clues of what this could be?