TSB - ECU UPGRADE ? STEERING LOGIC IMPROVEMENT -This bulletin has been revised to include additional information. This bulletin provides information related to the MDPS ECU software upgrade for some 2011-2014MY Optima (QF), produced from August 2, 2010 through July 27, 2014, and 2016-2018MY Sorento (UMa) vehicles, produced from October 27, 2014 through August 22, 2017, which may experience a notchy feel in the steering wheel. To correct this condition, the vehicle should be evaluated using the MDPS Effort Measurement Software detailed in the repair procedure starting on page 2 to determine whether an improved steering logic should be installed in the MDPS ECU, or if an MDPS column replacement is required. To determine whether the updated MDPS ECU reflash applies to a vehicle you are working on, or whether it has already been performed, verify ROM ID using the tables in this TSB.