Transmission Control Module

The hybrid gearbox control unit translates the nominal values of the hybrid master control unit (setpoint torque at the clutches and at the gearbox output). Thus the hybrid gearbox control unit, unlike the electronic transmission controls of other automatic transmissions, is no longer the primary controller for the gearbox functions, but an intelligent actuator control unit.

Some of responsibilities of the hybrid gearbox control unit are:

• Controlling the transmission oil circuit
• Operating and monitoring the multidisc clutches
• Ensuring cooling of the electric machines
• Reading sensor signals (output speed, transmission oil temperature and position of the parking lock)
• Monitoring the gearbox status and activating emergency programs if necessary
• Electronic immobilizer

Assign the transmission related functions to the control units.

Fig 1: Sectional View And Skeleton View Of Active Gearbox In E72

Courtesy of BMW OF NORTH AMERICA, INC.