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Adaptive Hydraulic Pressure Control




Adaptive Hydraulic Pressure Control:







The TCM simultaneously monitors engine speed along with the transmission output and on more recent systems the input (turbine) speed signal as well. This is necessary to determine the slip ratio and slip time during a shift. Slip ratio and slip time are influenced by production related differences between transmissions and by aging.

The comparison of target & real slip allow the TCM to perform the adaptive pressure control function by modifying the PWM control of the main pressure regulator solenoid increasing the clutch apply pressures to compensate for internal slip. The adaptive pressure control function optimizes the shift quality and increases the life span of the clutch plates.

The adaptive pressure control feature is not an AGS function.

Clearing adaptation values with the DIS or MoDiC only clears this pressure control adaptation values. Clearing these values can lead to bad shift quality until the shift pressure is again optimized by the adaptation.