Abstract: A continuously variable transmission (CVT) and a method is provided for CVT variator gross slip detection includes determining if a difference between a commanded variator speed ratio and a real variator speed ratio is greater than a predetermined variator speed ratio threshold, and then determining if a variator rate of change ratio is outside of predetermined variator rate of change ratio limits. Further, the method includes determining if a real torque capacity ratio is greater than a predetermined torque capacity ratio threshold, and performing at least one remedial action when the variator rate of change ratio is outside of predetermined variator rate of change ratio limits, and the real torque capacity ratio is greater than the predetermined torque capacity ratio threshold when the difference between the commanded variator speed ratio and the real variator speed ratio is greater than the predetermined variator speed ratio threshold.

Abstract: A variator control diagnostic system for an automobile vehicle includes a ratio error calculated by subtracting a transmission actual ratio from a commanded ratio. A first lookup table includes: an adjusted ratio error defined by adjusting the ratio error using a transmission fluid temperature value; and a rate curve compared against the adjusted ratio error to identify a lookup table output. A second lookup table provides a gross slip multiplier value based on a ratio bin torque offset value for a transmission ratio range. An adjusted error count is created by multiplying the gross slip multiplier value by the lookup table output.

Abstract: A continuously variable transmission (CVT) and a method is provided for CVT variator gross slip detection includes determining if a difference between a commanded variator speed ratio and a real variator speed ratio is greater than a predetermined variator speed ratio threshold, and then determining if a variator rate of change ratio is outside of predetermined variator rate of change ratio limits. Further, the method includes determining if a real torque capacity ratio is greater than a predetermined torque capacity ratio threshold, and performing at least one remedial action when the variator rate of change ratio is outside of predetermined variator rate of change ratio limits, and the real torque capacity ratio is greater than the predetermined torque capacity ratio threshold when the difference between the commanded variator speed ratio and the real variator speed ratio is greater than the predetermined variator speed ratio threshold.

Abstract: A switching valve control module selectively actuates a switching valve of a continuously variable transmission (CVT) either: (i) from a closed position to an open position; or (ii) from the open position to the closed position. The switching valve prevents and allows transmission fluid flow through a flow path between a transmission fluid pump and a pressure regulator valve of the CVT when the switching valve is in the closed position and the open position, respectively. An adjustment determination module determines a pressure adjustment when the switching valve actuates. A target pressure module determines a target pressure output from the pressure regulator valve. An adjusting module determines an adjusted target pressure based on the pressure adjustment and the target pressure. A regulator valve control module controls opening of the pressure regulator valve based on the adjusted target pressure.

Abstract: A switching valve control module selectively actuates a switching valve of a continuously variable transmission (CVT) either: (i) from a closed position to an open position; or (ii) from the open position to the closed position. The switching valve prevents and allows transmission fluid flow through a flow path between a transmission fluid pump and a pressure regulator valve of the CVT when the switching valve is in the closed position and the open position, respectively. An adjustment determination module determines a pressure adjustment when the switching valve actuates. A target pressure module determines a target pressure output from the pressure regulator valve. An adjusting module determines an adjusted target pressure based on the pressure adjustment and the target pressure. A regulator valve control module controls opening of the pressure regulator valve based on the adjusted target pressure.