Reverse Inhibitor Control
While the vehicle is moving forward, the PCM keeps shift solenoid valve E OFF. Shift valve E covers the port of line pressure (3') leading to the servo valve reverse position. The servo valve cannot be shifted to the reverse position, and hydraulic pressure is not applied to 4th clutch from the servo valve for reverse; as a result, power is not transmitted to the reverse direction.
NOTE:
When used, "left" or "right" indicates direction on the hydraulic circuit.