В двух словах - официальная прошивка блока управления трансмиссией, которая убирает пинок при переключении на пониженную передачу.
CM UPGRADE : TD/JD GAMMA 1.6MPI 6AT TCM LOGIC IMPROVEMENT
KFE16-52-E160-TD JD
СОДЕРЖАНИЕ
This bulletin provides information related to the Transmission Control Modules(TCM) software upgrade of some 2012~2013MY CERATO(TD) and 2013~2014MY C'eed(JD) GAMMA 1.6MPI 6AT vehicles, which may experience transmission shift shock while decelerate, to improve TCU logic.* This ECM upgrade should be performed only for customer complaint basis.[NOTE] - After upgrade is completed, reset the TCM adaptive learning values