My wife has a Merecedes-Benz A-Class bought just over a year ago from one of the car supermarkets. It still has outstanding warranty on it and runs well. It is low mileage, but has been used daily by ourselves. A recent service in a local garage revealed that the rear brake callipers were seized and the rear discs were corroded and pitted. The garage mechanic, who is a lifelong friend and very trustworthy, states that this work should be covered by the warranty of the car.

We have now had the car at the garage and Mercedes-Benz state that it is not covered. They asked if the car has been stood for a long time, which it hasn't with us. They state that the problem is natural causes and will not honour the work under warranty. Can you give me any advice?