Michigan's administrative rules R25.313a(16) prohibit the use of a bypass code for any reason.  The person assigned the BAIID should contact the interlock company prior to any repairs.  The repair facility can "fix" the vehicle using normal procedures.  The vehicle owner should provide the repair facility with a new mouthpiece if the mechanic will need to start the vehicle during the repair process.  Once the repair is completed the driver would submit the receipts to the department.  The department has never instructed a service center not to blow into a device, as anyone can start the vehicle using the BAIID.  It is the responsibility of the driver to provide documentation to the department verifying that he or she was no in possession of the vehicle during a particular time period.