815 ILCS 505/2M

No person engaged in the business of performing services on merchandise shall advertise such services as factory authorized services unless such services are performed by factory authorized personnel. Any person so advertising shall, upon request, supply proof of such authorization through manufacturer certification. Any person who violates this Section commits an unlawful practice within the meaning of this Act, and in addition to relief available under Section 7 of this Act, may be prosecuted for the commission of a Class C misdemeanor.