Torque converter

The mechanical power flow in the gearbox starts at the connection point between the torque converter and engine flywheel. When the engine is running, the converter housing (pump) turns with the engine speed. With rotation, the converter multiplies the engine torque and transfers it to the drive shaft. The drive shaft forms the main connection for mechanical operation of the gearbox.

Brief description of components

The sizes of converter are used:

230 mm for four-cylinder engines;

240 mm for six-cylinder engines;

The converter is equipped with a turbine wheel damper. The turbine wheel damper improves the values for noise, vibrations and roughness when the converter lockup clutch is actuated in the lower engine speed range.

The converter clutch leads to an improvement in the fuel consumption. Depending on the vehicle, engine and gearbox parameters, four operating modes are available:

• In the TCC OFF mode, the converter clutch does not engage and the torque converter has permanent slip (slip > 50 rpm).
  
• In the TCC ON mode (EC), the converter clutch is set to a slip of 40 rpm.
  
• In the TCC-ON mode (closed), there are two functions of the converter clutch:
  - low slip (0 to 10 rpm);
  - fully closed (no slip);
  

Relevant faults in the converter clutch

The following faults are treated in the test module:

• 56C1 converter clutch: stuck in open position
  
• 56C2 converter clutch: stuck in closed position