Fault detection for a torque converter

A method of operating an idling automatic transmission of a motor vehicle which has a torque converter, wherein the torque converter comprises at least one pump wheel and a turbine wheel which are designed to transmit torque hydrodynamically from one to the other, the method comprises at least the following steps:

• determinating (12) a rotation speed of the turbine wheel;
• determinating (14) a load on the motor of the motor vehicle;
• and
• recognizing (16) whether there is a blockage in the drive-train of the motor vehicle or whether the torque converter is running dry, as a function of the turbine rotation speed and the motor load detected.

A monitoring device (10) for an automatic transmission of a motor vehicle having a torque converter, wherein the torque converter comprises at least one pump wheel and a turbine wheel which are designed to transmit torque hydrodynamically from one to the other, wherein the monitoring device is designed, when the automatic transmission is idling, to:

• determine a rotation speed of the turbine wheel (12);
• determine a load on the motor of the motor vehicle (14);
• and
• as a function of the turbine rotation speed and the motor load determined, to recognize (16) whether there is a blockage in the drive-train of the motor vehicle or whether the torque converter is running dry.