Fail-safe gear-shifting control system for an automatic transmission

摘要

In a gear-shifting control system for an automatic transmission, gear-shifting is normally controlled according to main gear-shifting characteristics in which gear-shifting points are determined using the turbine rpm as a parameter. On the other hand, gear-shifting is effected according to backup gear-shifting characteristics which are determined using the vehicle speed as a parameter in case of failure of the part for detecting the turbine rpm.