System Components
Mechatronic Module: The mechatronic module is a combination of the hydraulic valve body and electronic control module which are installed in the oil sump. This is the first time the mechatronic module is used in a BMW automatic transmission. This offers the advantages of improved shift quality, increased driving comfort and increased reliability due to the reduced number of electrical connections and interfaces.
The hydraulic valve body contains valves, springs, dampers and electric solenoid valves. The electronic control module manages the complete electronic control of the transmission and is an integral part of the valve body (replaceable as a complete unit) . The electronic control module is completely sealed and oil tight.
The electronic-hydraulic transmission gearshifts in the GA6HP26Z are controlled by 3 solenoid valves and 6 electronic pressure control valves. These components are not separately replaceable at this time.
Solenoid Valves (MV): Three solenoid valves are mounted on the valve body and are 3/2- way valves, i.e. valves with three hydraulic connections and two electrically switch positions. The solenoid valves are activated by the electronic control module.
Electronic Pressure Control Valves (EDS): The electronic pressure control valves convert electrical current into a proportional hydraulic pressure. They are regulated by the electronic control module to activate the hydraulic valves (in the valve body) to the pistons in the clutch assemblies. Two types of EDS valves are used:
EDS with rising characteristic curve
- EDS valves 1, 3 and 6 are identified by a green cap.
- The rising characteristic curve starts at 0 mA = 0 bar, up to 700 mA = 4.6 bar.
- Operating voltage - 12 V
- Resistance at 20 °C = 5.05 Ohm
EDS with falling characteristic curve
- EDS valves 2, 4 and 5 are identified by a black cap.
- The falling characteristic curve starts at 700 mA = 0 bar, up to 0 mA = 4.6 bar.
- Operating voltage - 12 V
- Resistance at 20 °C = 5.05 Ohm