S (stall position): During this stage the turbine pace is zero as well as impeller is rotating; the efficiency in the stall point is minimum amount, close to 50%, which suggests that fifty percent of the power coming in the motor is missing through friction and dissipated as heat; at https://arthurimmlh.therainblog.com/33147021/the-2-minute-rule-for-torque-converter-clutch