TECHNICAL SERVICE BULLETIN: IBU LOGIC IMPROVEMENT FOR SMART KEY BATTERY DRAIN - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides the procedure to update the software logic of the Integrated Body Control Unit (IBU) system on some 2021-2022MY K5 (DL3a) vehicles produced from March 27, 2020 through May 12, 2022, which may exhibit excessive discharge of the smart key battery. Follow the procedure outlined in this publication to apply the improved logic to the "IBU" system using the KDS ECU Upgrade function as described in this bulletin and replace the batteries on both of the customer’s key fobs.
