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

GF27.60-P-2002PMB Function of Transmission Control
- TRANSMISSION 722.6 in MODELS 203.076 /276

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.

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 noticeable improvement in shift quality.

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.

It is possible to reach the engine rpm limit in the individual gears using full throttle and kick-down. 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

Electronic transmission control (EGS) takes place depending on the following factors:
^ The vehicle speed
^ The position of the selector lever
^ Program selection ("M/C/S")
^ Preselected shift range (with program selection "C/S")
^ Selected gear (with program selection "M")
^ The state of the transmission
^ Controller Area Network (data bus/CAN bus) (CAN) signals