Warranties never cover tyres, brake pads, brake discs, clutches, timing belts or ancillary belts because these are all parts expected to wear and need to be replaced. A water pump, an alternator, a power steering pump or a gearbox are not wearing parts, so these would normally be covered, but what is covered and what is not reduces as the car becomes older, making a warranty on a 12-year-old car of limited value anyway.