Certain 2018-2022MY Kona (OS) vehicles equipped with 2.0L engines and 4WD may exhibit transfer case oil leaks and/or an oil smell caused by the transfer case pinion oil seal overheating. This bulletin describes the procedure to update the 4WD electronic control module (ECU) and to inspect the transfer pinion area for leakage. If a leak is detected, the transfer case pinion oil seal will need to be replaced.