GF27.60-P-4013GZ Shift From 1 to 2, Function

GF27.60-P-4013GZ Shift from 1 to 2, function
- Transmission 722.9


Multidisk brake B2, multidisk brake B3 and multidisk clutch K3 are engaged in 1st gear. When shifting from 1st gear to 2nd gear, multidisk brake B3 is switched off and multidisk brake B1 is switched on.

The shift operation is started by the fully integrated transmission control (VGS) control unit (Y3/8n4). In the process multidisk brake B1 is filled and the pressure in multidisk brake B1 increased. Simultaneously the pressure in multi-disk brake B3 is reduced.

This involves a flowing transition. When the 2nd gear torque is reached, the engine speed must be adapted to the 2nd gear level (elevation phase). This speed adjustment is achieved by the pressure in multidisk brake B1 being increased and if necessary engine torque being reduced via the ME-SFI [ME] control unit (N3/10) or the CDI control unit (N3/9).