VTG Control Unit For xDrive: Notes

The VTG control unit regulates the locking torque at the multi-plate clutch in the transfer case in response to the following factors:

• Demand for required locking torque (comes from the DSC control unit)
• Condition of the transmission oil (calculated in the VTG control unit)
• Multi-plate clutch wear (calculated in the VTG control unit)
• Load on VTG actuator motor (calculated in the VTG control unit)
• Transmission oil temperature (calculated in the VTG control unit)

The VTG control unit supplies the following information to the DSC control unit:

• The locking torque currently set
• All calculated data

The locking torque is limited whenever needed in order to reduce the frictional work.