The Lemon Law only covers serious defects—those which substantially impair the use, safety or value of the vehicle. However, the law does not list specific defects which are considered substantial. You must be able to demonstrate how your vehicle has been substantially impaired. For example, to prove substantial value impairment, you could show that the retail value of your vehicle is significantly less than it would be without the defect. Although a defect may be annoying, it is not necessarily substantial.