Function Of Transmission Control

Transmission control is divided into the functions of electronic transmission control (ETC) and hydraulic transmission control.

Whilst the electronic transmission control (ETC) takes over gear selection and the adaptation of pressures to the torque to be transmitted, the power supply control of the automatic transmission takes place via the hydraulic elements of the electrohydraulic control unit. The oil supply to the hydraulic elements, such as the hydrodynamic torque converter, the shift elements and the hydraulic transmission control, is provided by way of an oil pump connected with the torque converter.

Furthermore ETC offers the advantage of a flexible adaptation to various vehicle and engine versions. The driver can choose between the two transmission modes "S" (sport program) and "C" (comfort program). These also provide different gear ratios for reverse gear.

The electronic transmission control (ETC) makes possible a precise adaptation of pressure to the respective operating conditions and to the engine output during the gear shift phase, resulting in a considerable improvement in shift quality. The engine speed limit can be reached in the individual gears at full throttle and kickdown.

The shift range can be changed in the forwards gears while driving, however the ETC prevents an unacceptably high engine speed by means of a downshift lockout device.

The ETC [EGS] control unit (N15/3) monitors and shifts depending on:

• The vehicle speed.
• The position of the selector lever.
• Accelerator pedal position.
• Program selection ("C/S").
• The state of the transmission.
• Controller Area Network (CAN) signals.

1. ETC Control Unit, Location/Task
   
   See ETC CONTROL UNIT, LOCATION/TASK  .
2. Electronic Control Unit, Location/Task/Design/Function
   
   See ELECTRIC CONTROL MODULE, LOCATION/TASK/DESIGN/FUNCTION  .
3. Starter Lockout Contact, Location/Task/Design/Function
   
   See STARTER LOCK-OUT CONTACT, LOCATION/TASK/DESIGN/FUNCTION  .
4. Temperature Sensor, Location/Task/Design/Function
   
   See TEMPERATURE SENSOR, LOCATION/TASK/DESIGN/FUNCTION  .
5. Speed Sensor, Location/Task/Function
   
   See WHEEL SPEED SENSOR, LOCATION/TASK/FUNCTION  .
6. Location/Task/Design/Function Of Oil Pump
   
   See LOCATION/TASK/DESIGN/FUNCTION OF OIL PUMP  .

Shift Buttons 

The transmission control is divided into the functions of electronic transmission control (ETC) and hydraulic transmission control.

Whilst the EGS takes over the gear selection and adaptation of pressures to the torque to be transmitted, the power supply control of transmission 722.6 takes place via the hydraulic elements of the electrohydraulic elements of the electrohydraulic control unit. The oil supply to the hydraulic elements, such as the hydrodynamic torque converter, the shift elements and the hydraulic transmission control, is provided by way of an oil pump connected with the torque converter.

The electronic transmission control (ETC) makes possible a precise adaptation of pressures to the respective operating conditions and to the engine output during the gearshift phase, resulting in a significant improvement in shift quality.

The ETC takes place as a function of:

• The vehicle speed.
• The position of the selector lever.
• Accelerator pedal position.
• Program selection ("M/C/S").
• Programmed shift range.
• Selected gear (with program selection "M").
• The state of the transmission.
• Controller Area Network (CAN) signals.

The ETC offers the advantage of a flexible adaptation to various vehicle and engine versions.

The driver can choose between 3 transmission modes "S" (Sport program), "C" (comfort program) and "M" (manual program). These also provide different gear ratios for reverse gear.

The engine speed limit can be reached in the individual gears at full throttle and kickdown. The shift range can be changed in the forwards gears while driving, however the ETC prevents an unacceptably high engine speed by means of a downshift lockout device.

1. ETC Control Unit, Location/Task
   
   See ETC CONTROL UNIT, LOCATION/TASK  .
2. Electric Control Unit, Location/Task/Design/Function
   
   See ELECTRIC CONTROL MODULE, LOCATION/TASK/DESIGN/FUNCTION  .
3. Location/Task/Design/Function Of Starter Interlock Contact
   
   See STARTER LOCK-OUT CONTACT, LOCATION/TASK/DESIGN/FUNCTION  .
4. Temperature Sensor, Location/Task/Design/Function
   
   See TEMPERATURE SENSOR, LOCATION/TASK/DESIGN/FUNCTION  .
5. Location/Task/Function Of RPM Sensor
   
   See WHEEL SPEED SENSOR, LOCATION/TASK/FUNCTION  .
6. Location/Task/Design/Function Of Oil Pump
   
   See LOCATION/TASK/DESIGN/FUNCTION OF OIL PUMP  .