Reverse Inhibitor Control

When R is selected while the vehicle is moving forward at a speed over 6 mph (10 km/h), the PCM commands shift solenoid valve D to remain OFF so that shift solenoid valve D pressure (SD) is not applied to the reverse control valve. Line pressure (3) stops at the reverse control valve, and is not applied to the servo valve. No power is transmitted to the reverse direction.

Fig 1: Hydraulic Pressure Distribution Circuit Diagram (Driving In Reverse Gear)

Courtesy of AMERICAN HONDA MOTOR CO., INC.