Hydraulic Control System (A340H) - Toyota Hilux Surf 1993 Owner's Manual

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Hydraulic Control System
1. Transmission
The hydraulic control system is composed of the oil pump, the valve body, the solenoid valves, and the clut–
ches and brakes, as well as the fluid passages which connect all of these components. Based on the
hydraulic pressure created by the oil pump, the hydraulic control system governs the hydraulic pressure ac–
ting on the torque converter clutch, clutches and brakes in accordance with the vehicle driving conditions.
There are three solenoid valves on the valve body. These solenoid valves are turned on and off by signals
from the ECM to operate the shift valves. These shift valves then switch the fluid passages so that fluid
goes to the torque converter clutch and planetary gear units.
2 Transfer
The hydraulic control system consists of a valve body, No.4 solenoid valve, a brake (B
(C3, C4) and passages that connect these elements. It hydraulically controls the planetary gear unit either
manually, or automatically by the ECM.
AUTOMATIC TRANSMISSION – Operation
) and two clutches
4