VOLUNTARY EMISSIONS SERVICE CAMPAIGN: IVT SOFTWARE LOGIC IMPROVEMENT AND/OR IVT REPLACEMENT (SC199) - 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 was previously referred as âÂÂSA424â or âÂÂELE 200âÂÂ.) This bulletin provides the procedure to update the Transmission Control Module (TCM) software logic and, if necessary, replace the Intelligent Variable Transmission (IVT) on certain 2019-2021MY vehicles listed in the chart below. The affected vehicles may exhibit the illumination of MIL with the DTC(s) listed below in addition to a lack of acceleration or delay in accelerating due to transmission slippage.