Reverse Inhibitor Control

While the vehicle is moving forward, the PCM keeps shift solenoid valve E remaining 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 reverse position, and hydraulic pressure is not applied to 4th clutch from servo valve for reverse; as a result, power is not transmitted to the reverse direction.

Fig 1: Identifying Hydraulic Flow In Reverse Inhibitor Control

Courtesy of AMERICAN HONDA MOTOR CO., INC.