Supersedes Technical Service Bulletin Group 00 number 12-43 dated December 21, 2012. If a 2012 - 2015 Audi A8 L W12 arrives at an Audi dealership and requires diagnosis or repair, a Repair Authorization must be obtained. Prior to any repair, a Technical Assistance Center (TAC) ticket must be created for engine and transmission concerns only. Routine maintenance and PDI do not require prior authorization or a Technical Assistance Center (TAC) ticket. These procedures are mandatory until further notice. Warranty repairs without repair authorization via a TAC contact will not be reimbursed.