Abstract: A method is provided for calibrating an automatic transmission with a torque converter clutch. In order to avoid that the torque converter clutch still has capacity even if the pressure is commanded to be zero without modifying the behavior of the torque converter clutch behavior of all the production, the torque converter clutch minimum offset transmissions are detected and only on these transmissions the torque converter minimum clamp pressure is decreased by a pressure step and the torque converter clutch coast adapt reference cell is increased.

Abstract: An automatic transmission is provided with a torque converter clutch (TCC) for regulating the slip between the engine speed and the transmission input speed and a method is provided for regulating the slip between the engine speed and the transmission input speed in an automatic transmission with a torque converter clutch. In order to improve the first time shift quality of transmissions, it is proposed that means are provided for learning the valve pressure offset. In first tests it could be stated that the first time shift quality can be considerably improved with a short test which takes place at the end of the vehicle production line. The longer the test time, the better the first time shift quality will be.

Abstract: A method is provided for calibrating an automatic transmission with a torque converter clutch. In order to avoid that the torque converter clutch still has capacity even if the pressure is commanded to be zero without modifying the behavior of the torque converter clutch behavior of all the production, the torque converter clutch minimum offset transmissions are detected and only on these transmissions the torque converter minimum clamp pressure is decreased by a pressure step and the torque converter clutch coast adapt reference cell is increased.