I gather this is a common problem, but was disheartened to see it on my 54 plate W211 after just 2 weeks of ownership. I bought the car from a Nissan franchise and I have a one year warranty with it. However, the battery is expressly excluded. Do you think I should ask them to cover it anyway or just cough up myself for a new one? Also, how do I know if it's the main battery or auxiliary? Don't know the first thing about testing them myself, and want to avoid a trip to the main dealers! Could Kwik fit do it, or an indy?