Ratio Adaptation

Ratio Adaptation

The transmission hydraulic/mechanical characteristics can be mapped inside the EMS2000. The curve of the input shaft speed verses output shaft speed looks like a straight line up to approximately 2,500 rpm. It then plateau's before rising in a curved manner. This profile will be a similar shape for all transmissions but its position plotted against engine speed will vary.

The EMS2000 knows the shape of the profile and monitors the actual engine speed relative to the mapped engine speed. The EMS2000 learns, through historical control, a new profile that is more representative of the actual transmission characteristics. The EMS2000 also monitors the amount this line moves from the mapped line, as long as this difference is within its tolerance band, the EMS2000 accepts the value and learns from it. If the actual value goes beyond the adaptive tolerance the EMS2000 will perform a reset. If the value still exceeds the adaptive tolerance band, the EMS2000 will store a fault code and place the transmission into its default position.

The figures quoted are only representative, due to the nature of the adaptation, these may or may not be correct. When setting the fast adaptation, the control system will initially target 5,000 rpm in order to learn the ratio control motor position at this engine speed. Once the vehicles power train is stable enough for an adaptation to take place, the ratio control motor position is noted and the control system will target 4,500 rpm. This process continues subsequently targeting 4,000, 3,500, 3,000, 2,500, 2,000, 1,900, 1,800, 1,700, 1,600, 1,500, 1,400. When the 1,400 rpm point has been adapted, normal operation will commence.
To set the fast adaptation procedure drive the car, on a level road, at around 60 km/h in ECVT drive mode, and then lift off the throttle.

As the vehicle decelerates (do not use the brakes) the adaptations will occur. If the vehicle speed drops too far before the process is complete, the engine speed will drop from its targeted speed back towards idle.

The instrument cluster display will continue to display the "X" character, and the transmission will not operate normally. If this happens, simply repeat the process by accelerating back to 60 km/h and lift off the throttle again to give the software a chance of learning the remaining points. When the procedure is complete, the display will return to normal.

On the completion of a fast adaptation, the lifetime adaptation strategy will commence, fine tuning the response of the control system for the transmission attached to a particular vehicle.

If either the EMS2000 or transmission is changed during the service life of the vehicle, the fast adaptation strategies must be reset, which in turn will reset the lifetime strategy so it starts learning from the new base point.