Michigan Compiled Laws, Chapter 257. Motor Vehicles § 257.1320

Sec. 20.(1) A certification as a specialty or master mechanic under this act takes effect on the date it is approved by the administrator and expires 1 year after that date. A specialty or master mechanic may annually renew his or her certification by submitting an application for renewal, accompanied by the certification fee described in section 30,  1 with the administrator on or before the expiration date of his or her then-current certification.

(2) A mechanic may continue to function as a certified mechanic after the expiration date of his or her then-current certification, pending approval of the renewal application by the administrator, if the renewal application and renewal fee are received by the administrator on or before the expiration date. If a renewal application and renewal fee are filed after the expiration date, the mechanic may temporarily engage in repairs without a certificate from the day on which the application and appropriate fee are received by the administrator, pending approval of the renewal application. The administrator shall charge a fee of 1- 1/2 times the normal renewal fee if the renewal application is received by the administrator after the expiration date.