Abstract: An automatic transmission control system for an automotive vehicle comprising fluid pressure operated clutch and brake servos that establish and disestablish plural torque delivery paths between the engine of the vehicle and a driven member, the control system having a pressure regulator for maintaining an optimum pressure level, a throttle solenoid valve, ratio shift controlling solenoid valves and means for replacing the functions of the throttle solenoid valve and the shift controlling solenoid valves in the event that a control voltage failure or a valve malfunction should occur.

Abstract: A control system for an automatic transmission including pressure actuated clutches and brakes adapted to control ratio changes in a planetary gear system comprising multiple function shift control valves disposed between a pressure source and pressure actuated servos for the clutches and brakes and solenoid valves under the control of a microprocessor for developing solenoid valve signals that control actuation of the shift control valves, the shift control valves being interactive, one with respect to the other, to effect multiple shift functions in response to selective actuation of the solenoid valves whereby the number of solenoid valves required is reduced and the hydraulic circuitry for the valve elements is simplified.

Abstract: A locking mechanism for demountably securing a solenoid valve assembly within a receptacle in the wall of a transmission housing. A retention means is presented from the frame of the solenoid valve assembly cooperatively to interact with various blocking faces on a pillar means presented from the transmission housing and located adjacent to the receptacle. A stop lug, an engaging surface and a latching dog are each presented from the retention means. First, second and third blocking faces are presented from the pillar means. Engagement of the stop lug with the first blocking face limits the angular range through which the solenoid valve assembly may be rotated within the receptacle. When the stop lug engages the first blocking face, the engaging surface is disposed in opposition to the second blocking face to preclude withdrawal of the solenoid valve assembly from the receptacle.