Automatic transmission control system for vehicle, has unit controlling transmission to start retrogradation if speed of vehicle exceeds entry speed in situation of descent with predetermined variation

摘要

The system (3) has measurement unit storing a longitudinal entry speed in a situation of descent (Vmin) when a vehicle enters the situation. A unit compares a current speed (V) of the vehicle with an entry speed in the situation of descent (Vmin). A unit controls the transmission to start a retrogradation if the speed (V) exceeds the entry speed (Vmin) with a predetermined variation (VS). An Independent claim is also included for a vehicle comprising an engine and an automatic transmission.