Control of the automatic transmission

The control of the automatic transmission consists essentially of the gearbox control unit and the hydraulic selector unit.

More detailed functional description, see BMW Technology:

TIS -> Document -> SI Technology -> SBT Number:

• 2401 05 106
  

Gearbox management

The gearbox control is divided mainly into the following components:

• Gearbox control unit:
  
  • Power supply for solenoid valves and electronic pressure actuators
    
  • Evaluation of the sensor system
    
• Gearbox sensor system:
  
  • Sensor for the gearbox input speed
    
  • Sensor for the gearbox output speed
    
  • Gearbox oil temperature sensor
    
• Gearbox actuator system:
  
  • Solenoid valves
    
  • Electronic pressure actuators
    
• Gearbox connector for connection to the gearbox and vehicle wiring harness
  

Gearbox control unit

On this gearbox, the gearbox control unit is fitted as a separate control unit. Firstly, it evaluates the sensors electronically and directly activates the actuators of the hydraulic selector unit. A temperature sensor additionally monitors the gearbox oil temperature.

Hydraulic selector unit

The hydraulic selector unit in the gearbox is similar to the hydraulic modules commonly used until now in gearboxes. It contains the hydraulic actuator system (solenoid valves, electronic pressure actuators) of the gearbox.