Shifting N to D (1st gear), function - GF27.60-P-4014CWQ

TRANSMISSION 722.9 in MODEL 204.0 up to Model Year 8 

When the center shifter console is in position "N", multidisk brake B3 and multidisk clutch K3 are engaged. When the electronic selector lever module control unit (N15/5) shifts from position "N" to position "D", the feed to multidisk brake B2 is enabled by the selector valve. The fully integrated transmission control unit (Y3/8n4) actuates multidisk brake control solenoid valve B2 (Y3/8y6) and multidisk brake B2 is filled with transmission oil. The fully integrated transmission control unit uses the rpm difference (actual slip) between the engine speed and turbine speed to detect whether multidisk brake B2 is full. The multidisk brake control solenoid valve B2 actuates the regulating valve B2/BR which converts the applied working pressure into shift pressure and passes it on to multidisk brake B2.

In the fully integrated transmission control unit, the required slip (specified slip) is stored for the respective gear. Depending on this, the control pressure is changed to regulating valve B2/BR via multidisk brake control solenoid valve B2. The shift pressure produced by the regulating valve B2/BR depends on the geometry of the regulating valve B2/BR. The pressure in multidisk brake B2 is changed until the specified slip stored in the fully integrated transmission control unit is reached.