This bulletin provides the procedure to improve the logic of the Transmission Control Unit (TCU) on some 2018MY Stinger (CK) 2.0T and 3.3T vehicles, equipped with Shift-by-Cable (SBC) and produced from September 29, 2017 through February 7, 2018. These vehicles may experience improper 1st gear engagement when moving the shifter in a fast or abrupt manner from "Park" to "Sport Mode". To correct this condition, apply the improved logic to the TCU using the KDS ECU Upgrade function as described in this bulletin. To confirm that the latest reflash has been applied to vehicle you are working on, verify the ROM ID using the table on page 2 of this bulletin. Before conducting the procedure, verify that the vehicle is included in the list of affected VINs.