Patent ID: 8265838

Claim:
A system in a transmission for calibrating an input signal sent to a pressure control device with an output pressure of a hydraulic fluid provided by the pressure control device, the system comprising: a temperature sensor for sensing a temperature of the hydraulic fluid within the transmission; a pressure control device for controlling an output pressure of the hydraulic fluid; and a controller in communication with the temperature sensor and the pressure control device, the controller having control logic including a first control logic for providing a target threshold that comprises a first actual input signal operable to produce a first output pressure, a second control logic for providing a lower estimated threshold that comprises a first estimated input signal estimated to produce a second output pressure, a third control logic for providing an estimated signal-to-pressure relationship that provides a plurality of estimated input signals estimated to produce a plurality of output pressures, the estimated signal-to-pressure relationship including the target threshold and the lower estimated threshold, a fourth control logic for determining a lower target threshold that comprises a second actual input signal required to produce the second output pressure, a fifth control logic for calculating a signal offset from the difference between the second actual input signal and the first estimated input signal, and a sixth control logic for determining a calibrated signal-to-pressure relationship that provides a plurality of calibrated input signals operable to produce the plurality of output pressures, wherein the plurality of calibrated input signals are proportionally offset from the plurality of estimated input signals using a proportional value of the signal offset.