I recently bought a new Nissan Tiida, which has been fitted with aftermarket power windows by the dealer. So far three of the window cables have been replaced due to breakage. Are the windows covered under the Nissan warranty, which is three years; as the installer claims I only get one year.
No, Nissan's warranty only covers the car as it was when it left the Nissan factory; the aftermarket windows will carry their own warranty from their manufacturer. When it comes to the windows you need to deal with the dealer.