Hydraulic operation – R – REVERSE

Hydraulic operation – R – REVERSE

The flow of fluid through the torque converter circuit is the same as in N. Fluid (1) from the oil pump flows through the manual valve and becomes line pressure (3). It then flows through the 1 – 2 shift valve to the servo valve (3), causing the shift fork shaft to be moved in the reverse direction.

Under this condition, the shift control solenoid valve A is turned on whereas the valve B is turned off as in 3rd speed in D4 or D3. As a result, the 1 – 2 shift valve is also moved to the left. The fluid (3') will flow through the servo valve and manual valve to the 4th clutch; power is transmitted through the 4th clutch.

Reverse Inhibitor Control

If R is selected whilst the vehicle is moving forward at a speed over 6 mph (10 km/h), the transmission control module outputs 1st signal (A:OFF, B:ON), and the 1 – 2 shift valve is moved to the right side. The line pressure (3) is intercepted by the 1 – 2 shift valve; consequently, power is not transmitted as the 4th clutch and servo valve are not operated.

Key to hydraulic flow diagram