Patent attributes
A hydraulic control system for a motor vehicle transmission includes a pressure regulation subsystem in fluid communication with a pump for providing pressurized hydraulic fluid. A manual valve assembly is in direct fluid communication with the pressure regulation subsystem, and is moveable by an operator of the motor vehicle between at least park, neutral, drive, and reverse positions. A default disable valve assembly is in direct fluid communication with the manual valve assembly, a default disable solenoid, and a default select valve assembly. The manual valve assembly is in direct fluid communication with the default disable valve assembly which is in direct fluid communication with the default disable solenoid and the default select valve assembly. The default disable solenoid enables the default disable valve assembly to enable three default modes of operation and the default select valve assembly selects between two of the three default modes of operation.
