Gear shift, function - GF27.60-P-2000GGA
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 shift operation, general
- Circuit 87 ON
- Circuit 61 ON
- Engine RPM from CDI control unit or from ME-SFI [ME] control unit
- Vehicle speed v > 0 km/h
- Transmission not in limp-home mode
Shift operation, general
The electric controller unit (VGS) converts the electrical signals coming from the fully integrated transmission control unit (VGS) into hydraulic signals. The selector lever positions "P, R, N, D" are sent by the electronic selector lever module control unit over the drive train CAN.
The CDI control unit or the ME-SFI [ME] control unit sends the information to the drive train CAN. The electronic selector lever module control unit routes the selector lever position taking various pieces of information into account to the fully integrated transmission control unit (VGS).
The shift range is shown in the instrument cluster.
Although the shift range can be changed in the forward gears while driving, the fully integrated transmission control unit (VGS) prevents a shift operation if the engine speed is too high or too low.
Function sequence for shifting
(taking shifting from 1 to 2 as an example)
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 disengaged and multidisk brake B1 is engaged.
The shift operation is started by the fully integrated transmission control unit (VGS). Here, the multidisk brake B1 is filled and the pressure in multidisk brake B1 is increased continuously. 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 the multidisk brake B1 being increased and, if necessary, by the CDI control unit or ME-SFI control unit reducing engine torque.
A forced downshift occurs at excessively low RPM and a forced upshift occurs at an excessively high RPM.
When the vehicle is stationary the transmission automatically shifts into 1st gear. It is possible to start off both in 1st or 2nd gear.
| Emergency default mode, function | GF27.60-P-3012GGA | ||
| Engage gear range, function | GF27.60-P-3009GGA | ||
| Torque converter lockup clutch control, function | GF27.20-P-3002GGA | ||
| Torque converter lockup clutch control pressure, function | GF27.60-P-3019GGA | ||
| Working/lubrication/shift pressure, function | GF27.60-P-3024GGA | ||
| Control valve pressure, function | GF27.60-P-3017GGA |