Engage gear range, function - GF27.60-P-3009GGA

TRANSMISSION 722.902 in MODEL 463.306/336/346 up to 31.5.12 as of Model Year 2011/YoM 10 

TRANSMISSION 722.904 in MODEL 463.202/222/236/237 up to 31.5.12 as of Model Year 2009/YoM 08 

TRANSMISSION 722.902 in MODEL 463.303/340/341 up to 31.5.12 as of Model Year 2009/YoM 08 

Function requirements for Engage gear range, general 

• Circuit 87 ON
• Circuit 61 ON

Engage gear range, general 

Each gear change is triggered by the fully integrated transmission control system. In the process one component group is assigned to each shift operation.

One component group consists of the respective control solenoid valve, the regulating valve involved, the responsible shift valve and the necessary multi-disk brake or necessary multi-disk clutch.

The pressure in the multidisk brake or multidisk clutch to be engaged is increased constantly while at the same time the pressure in the multidisk brake or multidisk clutch to be disengaged is reduced. In the process a flowing transition is involved, but nevertheless the components affected are actuated directly and as a result enable downshifting via several gears.

Function sequence for engaging gear range 

Shift operation N to D (1st gear) 

In the "N" position of the electronic selector lever module control unit(N15/5) the multidisk brake B3 and multidisk clutch K3 are shifted. Shifting from the "N" position to the "D" position, enables access to the multidisk brake B2. The fully integrated transmission control unit (VGS) (Y3/8n4) actuates brake control solenoid valve B2 (Y3/8y6) and multidisk brake B2 is filled with 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 brake control solenoid valve B2 actuates the regulating valve B2 or BR which converts the applied working pressure into shift pressure and passes it on to the multidisk brake B2

In the fully integrated transmission control unit (VGS), the required slip (specified slip) is stored for the respective gear. The control pressure on regulating valve B2 or BR is changed via brake control solenoid valve B2 depending on this. 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 (VGS) is reached.

	Component description for electronic selector lever module control unit	N15/5	GF27.60-P-5163GGA
	Component description for fully integrated transmission control unit	Y3/8n4	GF27.60-P-5165GGA