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Controlling The Shift Solenoids When Shifting

Shifting and the lock-up function is controlled by activating the solenoids in a specific pattern. The solenoids S1-S5 determine which gear is to be used and the SLS, SLU and SLT solenoids determine engagement by adjusting hydraulic line pressure. The basic parameters for the different shifting points are the accelerator pedal (AP) position and the vehicle speed. The shift quality is decided by the control of torque.

The pressurization of the clutches and the brakes are adjusted by reading the changes of the speed of the transmission input shaft during the shifting process and comparing them to the values calculated in the transmission control module (TCM).

Two shifting patterns can be selected, normal conditions and winter mode (selected using the button).

In normal mode shifting and lock-up occur at relatively low speeds to reduce fuel consumption. In the event of rapid accelerator pedal movements, the transmission control module (TCM) automatically shifts to sport mode.

Shifting patterns 

Gear Activated solenoid
S1  S2  S3  S4  S5  SLS 
1 ON ON ON OFF OFF OFF
2 OFF OFF ON OFF OFF ON
3 OFF OFF ON ON OFF ON
4 OFF OFF OFF ON OFF ON
5 OFF ON OFF ON OFF ON
R OFF OFF ON OFF ON OFF