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GF27.60-P-2002RM Function of Transmission Control



GF27.60-P-2002RM Function of transmission control
- Transmission 722.6
- up to 31.5.03 [model 209.376]
- up to 31.8.03 [models 211.076, 230.474]


Transmission control is divided into the electronic and hydraulic transmission control functions.

Whilst the electronic transmission control (ETC) takes over gear selection and the adaptation of pressures to the moment to be transmitted, the power supply control of the 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.

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

Furthermore, electronic transmission control (ETC) offers the advantage of flexible adaptation to various vehicle and engine versions.

The driver can choose between the three transmission modes "S" (standard program), "W" (winter program) and "M" (manual program). These also provide different gear ratios for reverse gear. It is possible to reach the rpm limit in the individual gears at full throttle and using kick-down. While driving, the shift range can be changed in the forwards gears, however the electronic transmission control (ETC) prevents an unacceptably high engine rpm by means of downshift protection.

Electronic transmission control (ETC)operates in relation to
^ The vehicle speed
^ The position of the selector lever
^ Accelerator pedal position
^ Program selection ("M/W/S")
^ The pre selected shift range (with program selection "W/S")
^ The selected gear (with program selection "M")
^ The state of the transmission
^ CAN signals