Toyota Yaris: Power Steering System / System Description

SYSTEM DESCRIPTION

DESCRIPTION

The power steering system generates torque through the operation of the motor and the reduction gear installed on the column shaft in order to assist steering effort.

The power steering ECU assembly determines the direction and the amount of assist power in accordance with the vehicle speed signals and signals from the torque sensor built into the electric power steering column sub-assembly. As a result, the power steering ECU assembly adjusts the steering effort so that it is lighter during low speed driving and heavier during high speed driving.

(a) Power steering ECU:

The power steering ECU calculates assist power based on steering torque signals from the torque sensor and vehicle speed signals from the skid control ECU (brake actuator assembly).

(b) Torque sensor:

The torque sensor detects the steering effort generated when the steering wheel is turned and converts it to an electrical signal.

(c) Power steering motor:

The power steering motor generates torque in accordance with the current from the power steering ECU to assist the steering effort.