815 ILCS 340/6
It shall be an affirmative defense to any claim under this Act that (1) an alleged nonconformity does not substantially impair such use, or (2) a nonconformity is the result of abuse or neglect, or of modifications or alterations of the farm implement not authorized by the manufacturer.
(from Ch. 5, par. 1556)
(Source: P.A. 85-894.)