Mich. Comp. Laws § 257.1303

Sec. 3. Unless the means of doing or engaging in a motor vehicle repair business including the operating of a motor vehicle repair facility is adopted for the purposes of evading this act, and except as otherwise provided in this act, this act does not apply to gasoline service stations exclusively engaged in the business of selling motor fuel and lubricants. However, a person, including a gasoline service station, that provides minor repair services or activities incidental to the business of selling motor fuel and lubricants is a motor vehicle repair facility and is subject to this act, except that an employee of the person may perform minor repair services without a certification or permit from the department under this act.