Some vehicles are equipped with automatic transmissions that have a torque converter between the engine and transmission. This increases the torque output of the engine and there is greater control of the rear wheels.
There is a connection between the motor and the transmission by means of a fluid coupling system which multiplies the torque until the speeds are equalized, thus creating a stall speed. At that speed, the actual RPM of the engine and the input RPM of the transmission are different, about 90% efficient.
The Powertrain Control Module (PCM) or Transmission Control Module (TCM), depending on the model, controls the Torque Converter Clutch (TCC) solenoid to direct the hydraulic fluid and engage the torque converter clutch, thus creating a solid coupling, as well as increasing efficiency.
When the DTC code P0741 OBD2 is set it means that the TCM or PCM has detected a fault in the TCC (Torque converter clutch) solenoid circuit.